ClinVar Genomic variation as it relates to human health
NM_002693.3(POLG):c.1399G>A (p.Ala467Thr)
The aggregate germline classification for this variant, typically for a monogenic or Mendelian disorder as in the ACMG/AMP guidelines, or for response to a drug. This value is calculated by NCBI based on data from submitters. Read our rules for calculating the aggregate classification.
Stars represent the aggregate review status, or the level of review supporting the aggregate germline classification for this VCV record. This value is calculated by NCBI based on data from submitters. Read our rules for calculating the review status. The number of submissions which contribute to this review status is shown in parentheses.
No data submitted for somatic clinical impact
No data submitted for oncogenicity
Variant Details
- Identifiers
-
NM_002693.3(POLG):c.1399G>A (p.Ala467Thr)
Variation ID: 13496 Accession: VCV000013496.93
- Type and length
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single nucleotide variant, 1 bp
- Location
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Cytogenetic: 15q26.1 15: 89327201 (GRCh38) [ NCBI UCSC ] 15: 89870432 (GRCh37) [ NCBI UCSC ]
- Timeline in ClinVar
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First in ClinVar Help The date this variant first appeared in ClinVar with each type of classification.
Last submission Help The date of the most recent submission for each type of classification for this variant.
Last evaluated Help The most recent date that a submitter evaluated this variant for each type of classification.
Germline Apr 4, 2013 Oct 20, 2024 Mar 27, 2024 - HGVS
-
Nucleotide Protein Molecular
consequenceNM_002693.3:c.1399G>A MANE Select Help Transcripts from the Matched Annotation from the NCBI and EMBL-EBI (MANE) collaboration.
NP_002684.1:p.Ala467Thr missense NM_001126131.2:c.1399G>A NP_001119603.1:p.Ala467Thr missense NC_000015.10:g.89327201C>T NC_000015.9:g.89870432C>T NG_008218.2:g.12595G>A LRG_765:g.12595G>A LRG_765t1:c.1399G>A LRG_765p1:p.Ala467Thr P54098:p.Ala467Thr - Protein change
- A467T
- Other names
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p.A467T:GCC>ACC
- Canonical SPDI
- NC_000015.10:89327200:C:T
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Functional
consequence HelpThe effect of the variant on RNA or protein function, based on experimental evidence from submitters.
- -
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Global minor allele
frequency (GMAF) HelpThe global minor allele frequency calculated by the 1000 Genomes Project. The minor allele at this location is indicated in parentheses and may be different from the allele represented by this VCV record.
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0.00020 (T)
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Allele frequency
Help
The frequency of the allele represented by this VCV record.
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The Genome Aggregation Database (gnomAD) 0.00068
1000 Genomes Project 0.00020
1000 Genomes Project 30x 0.00031
The Genome Aggregation Database (gnomAD), exomes 0.00051
Exome Aggregation Consortium (ExAC) 0.00052
Trans-Omics for Precision Medicine (TOPMed) 0.00063
- Links
Genes
Gene | OMIM | ClinGen Gene Dosage Sensitivity Curation |
Variation Viewer
Help
Links to Variation Viewer, a genome browser to view variation data from NCBI databases. |
Related variants | ||
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HI score
Help
The haploinsufficiency score for the gene, curated by ClinGen’s Dosage Sensitivity Curation task team. |
TS score
Help
The triplosensitivity score for the gene, curated by ClinGen’s Dosage Sensitivity Curation task team. |
Within gene
Help
The number of variants in ClinVar that are contained within this gene, with a link to view the list of variants. |
All
Help
The number of variants in ClinVar for this gene, including smaller variants within the gene and larger CNVs that overlap or fully contain the gene. |
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POLG | - | - |
GRCh38 GRCh37 |
1868 | 3010 |
Conditions - Germline
Condition
Help
The condition for this variant-condition (RCV) record in ClinVar. |
Classification
Help
The aggregate germline classification for this variant-condition (RCV) record in ClinVar. The number of submissions that contribute to this aggregate classification is shown in parentheses. (# of submissions) |
Review status
Help
The aggregate review status for this variant-condition (RCV) record in ClinVar. This value is calculated by NCBI based on data from submitters. Read our rules for calculating the review status. |
Last evaluated
Help
The most recent date that a submitter evaluated this variant for the condition. |
Variation/condition record
Help
The RCV accession number, with most recent version number, for the variant-condition record, with a link to the RCV web page. |
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Pathogenic (4) |
criteria provided, multiple submitters, no conflicts
|
Mar 30, 2023 | RCV000014440.33 | |
Pathogenic (3) |
criteria provided, multiple submitters, no conflicts
|
Aug 4, 2022 | RCV000014441.40 | |
Pathogenic (1) |
no assertion criteria provided
|
Feb 11, 2011 | RCV000014442.35 | |
Pathogenic (8) |
criteria provided, multiple submitters, no conflicts
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Mar 27, 2024 | RCV000014443.48 | |
Pathogenic (16) |
criteria provided, multiple submitters, no conflicts
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Mar 1, 2024 | RCV000188658.60 | |
Pathogenic (2) |
criteria provided, multiple submitters, no conflicts
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Mar 26, 2020 | RCV000184011.10 | |
Pathogenic (2) |
criteria provided, multiple submitters, no conflicts
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Dec 6, 2022 | RCV000347876.13 | |
Pathogenic (1) |
criteria provided, single submitter
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Dec 28, 2021 | RCV000515354.10 | |
Pathogenic (2) |
no assertion criteria provided
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Apr 7, 2017 | RCV000508942.10 | |
Pathogenic (1) |
criteria provided, single submitter
|
- | RCV001004604.8 | |
Pathogenic (4) |
criteria provided, multiple submitters, no conflicts
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Jun 27, 2018 | RCV001095683.13 | |
Pathogenic (1) |
criteria provided, single submitter
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May 7, 2019 | RCV001198082.9 | |
Pathogenic (1) |
criteria provided, single submitter
|
Nov 8, 2018 | RCV001376079.9 | |
Pathogenic (1) |
criteria provided, single submitter
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Jul 21, 2020 | RCV001731286.8 | |
Pathogenic (1) |
criteria provided, single submitter
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Aug 23, 2021 | RCV001813983.11 | |
Pathogenic (1) |
criteria provided, single submitter
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May 1, 2020 | RCV001847600.10 | |
Pathogenic (1) |
criteria provided, single submitter
|
- | RCV002273931.9 | |
Pathogenic (1) |
criteria provided, single submitter
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Oct 22, 2021 | RCV002316195.9 | |
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Submissions - Germline
Classification
Help
The submitted germline classification for each SCV record. (Last evaluated) |
Review status
Help
Stars represent the review status, or the level of review supporting the submitted (SCV) record. This value is calculated by NCBI based on data from the submitter. Read our rules for calculating the review status. This column also includes a link to the submitter’s assertion criteria if provided, and the collection method. (Assertion criteria) |
Condition
Help
The condition for the classification, provided by the submitter for this submitted (SCV) record. This column also includes the affected status and allele origin of individuals observed with this variant. |
Submitter
Help
The submitting organization for this submitted (SCV) record. This column also includes the SCV accession and version number, the date this SCV first appeared in ClinVar, and the date that this SCV was last updated in ClinVar. |
More information
Help
This column includes more information supporting the classification, including citations, the comment on classification, and detailed evidence provided as observations of the variant by the submitter. |
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Pathogenic
(Dec 16, 2013)
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criteria provided, single submitter
Method: clinical testing
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Progressive external ophthalmoplegia, autosomal dominant
Affected status: yes
Allele origin:
maternal
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Courtagen Diagnostics Laboratory, Courtagen Life Sciences
Accession: SCV000236534.2
First in ClinVar: Jul 02, 2015 Last updated: Jul 02, 2015 |
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Pathogenic
(Apr 24, 2014)
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criteria provided, single submitter
Method: clinical testing
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Cerebellar ataxia infantile with progressive external ophthalmoplegia
(Autosomal recessive inheritance)
Affected status: not provided
Allele origin:
germline
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Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Study: CSER-MedSeq
Accession: SCV000245651.1 First in ClinVar: Sep 14, 2015 Last updated: Sep 14, 2015 |
Comment:
The Ala467Thr variant in POLG has been reported in >20 individuals with mitochondrial disease in both the homozygous and compound heterozygous states, with symptoms ranging … (more)
The Ala467Thr variant in POLG has been reported in >20 individuals with mitochondrial disease in both the homozygous and compound heterozygous states, with symptoms ranging from progressive external ophthalmoplegia to intractable epilepsy to Alpers syndrome (van Goethem 2001, van Goethem 2004, Ferrari 2005, Winterthun 2005, Lax 2012, Scalais 2012, Uusimaa 2012). This variant has also been identified in 0.14% (12/8598) of European American chromosomes and 0.09% (4/4400) of African American chromosomes by the NHLBI Exome Sequencing Project (http://evs.gs.washington.edu/EVS/. In vitro functional studies have shown that the Ala467Thr variant leads to loss of wild-type activity and binding affinity (Chan 2005, Luoma 2005). In summary, this variant meets our criteria to be classified as pathogenic (http://pcpgm.partners.org/LMM). (less)
Number of individuals with the variant: 1
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Pathogenic
(Jun 14, 2016)
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criteria provided, single submitter
Method: clinical testing
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POLG-Related Spectrum Disorders
Affected status: unknown
Allele origin:
germline
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Illumina Laboratory Services, Illumina
Accession: SCV000394291.2
First in ClinVar: Dec 06, 2016 Last updated: Dec 06, 2016 |
Comment:
The c.1399G>A (p.Ala467Thr) variant is well described in the literature as one of the most common mutations associated with POLG-related disorders, particularly Alpert-Huttenlocher syndrome (Chan … (more)
The c.1399G>A (p.Ala467Thr) variant is well described in the literature as one of the most common mutations associated with POLG-related disorders, particularly Alpert-Huttenlocher syndrome (Chan et al. 2005; Cohen et al. 2014; Rajakulendran et al. 2016). Across a selection of the literature, the p.Ala467Thr variant has been identified in at least 52 patients including 15 in a homozygous state and 37 in a compound heterozygous state (van Goethem et al. 2001; Tzoulis et al. 2006; Tang et al. 2011; Uusimaa et al. 2013; Rajakulendran et al. 2016). In addition the variant has been found in 154 out of 498 patient alleles (31%) (Tang et al. 2011). The p.Ala467Thr variant was found in three out of 229 controls in one study and is reported at a frequency of 0.001400 in the European American population of the Exome Sequencing Project. Functional studies have demonstrated that the p.Ala467Thr variant results in a drastically reduced polymerase gamma activity to 4 - 18% of the wild type, reduced DNA binding capability to 14% of the control value, and a reduction in a processivity due to an impaired interaction with the accessory subunit of the enzyme which then slows the rate of DNA synthesis (Chan et al. 2005; Luoma et al. 2005). Based on the collective evidence the p.Ala467Thr variant is classified as pathogenic for POLG-Related Disorders. (less)
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Pathogenic
(Jan 03, 2018)
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criteria provided, single submitter
Method: clinical testing
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Progressive sclerosing poliodystrophy
(Autosomal recessive inheritance)
Affected status: yes
Allele origin:
unknown
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Undiagnosed Diseases Network, NIH
Study: Undiagnosed Diseases Network (NIH), UDN
Accession: SCV000837702.1 First in ClinVar: Oct 10, 2018 Last updated: Oct 10, 2018 |
Comment:
This is the most common pathogenic variant described in cases of Alpers-Huttenlocher syndrome (Mitochondrial DNA depletion syndrome 4A (Alpers type), MIM 203700), we have sparse … (more)
This is the most common pathogenic variant described in cases of Alpers-Huttenlocher syndrome (Mitochondrial DNA depletion syndrome 4A (Alpers type), MIM 203700), we have sparse records on the patient's phenotype (long deceased), but it seems a very reasonable clinical fit, albeit perhaps somewhat late onset (age 11). (less)
Number of individuals with the variant: 1
Clinical Features:
Short stature (present) , Skeletal muscle atrophy (present) , Behavioral abnormality (present) , Mental deterioration (present) , Status epilepticus (present) , Brain atrophy (present) , … (more)
Short stature (present) , Skeletal muscle atrophy (present) , Behavioral abnormality (present) , Mental deterioration (present) , Status epilepticus (present) , Brain atrophy (present) , Hepatic fibrosis (present) , Hepatic steatosis (present) , Abnormality of the pancreas (present) , Recurrent hypoglycemia (present) , Decreased serum ceruloplasmin (present) , Hypocupremia (present) , Decreased urinary copper concentration (present) (less)
Age: 10-19 years
Sex: male
Ethnicity/Population group: White
Tissue: Fibroblasts
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Pathogenic
(Dec 21, 2017)
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criteria provided, single submitter
Method: clinical testing
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not provided
Affected status: unknown
Allele origin:
germline
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Eurofins Ntd Llc (ga)
Accession: SCV000331833.4
First in ClinVar: Dec 06, 2016 Last updated: Aug 04, 2018 |
Number of individuals with the variant: 10
Sex: mixed
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Pathogenic
(Jun 27, 2018)
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criteria provided, single submitter
Method: clinical testing
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POLG-related condition
(Autosomal recessive inheritance)
Affected status: yes
Allele origin:
inherited
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Undiagnosed Diseases Network, NIH
Accession: SCV000863407.1
First in ClinVar: Dec 16, 2018 Last updated: Dec 16, 2018 |
Comment:
Submitting this as a novel interpretation as this patient's phenotype does not fit any of the POLG-associated conditions listed in OMIM. This is a different … (more)
Submitting this as a novel interpretation as this patient's phenotype does not fit any of the POLG-associated conditions listed in OMIM. This is a different observation than SCV000837701.1 where we observed this variant in a compound heterozygous state with another POLG variant and the patient fit the POLG-related conditions listed in OMIM. (less)
Number of individuals with the variant: 1
Clinical Features:
Sensory ataxia (present) , Seizures (present) , Postural tremor (present) , Polyneuropathy (present) , Myoclonus (present) , Limb dysmetria (present) , Kinetic tremor (present) , … (more)
Sensory ataxia (present) , Seizures (present) , Postural tremor (present) , Polyneuropathy (present) , Myoclonus (present) , Limb dysmetria (present) , Kinetic tremor (present) , Impaired vibratory sensation (present) , Impaired proprioception (present) , Hyporeflexia (present) , EEG abnormality (present) , Bipolar affective disorder (present) , Acute hepatic failure (present) (less)
Age: 30-39 years
Sex: male
Ethnicity/Population group: White
Tissue: blood
Testing laboratory: HudsonAlpha Clinical Services Lab, LLC, HudsonAlpha Clinical Services Lab, LLC
Date variant was reported to submitter: 2018-06-17
Testing laboratory interpretation: Pathogenic
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Pathogenic
(-)
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criteria provided, single submitter
Method: clinical testing
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Progressive sclerosing poliodystrophy
Mitochondrial DNA depletion syndrome 4b
Affected status: unknown
Allele origin:
germline
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Baylor Genetics
Accession: SCV001163774.1
First in ClinVar: Feb 29, 2020 Last updated: Feb 29, 2020 |
|
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Pathogenic
(-)
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criteria provided, single submitter
Method: research
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POLG-related disorders
Affected status: no
Allele origin:
germline
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UNC Molecular Genetics Laboratory, University of North Carolina at Chapel Hill
Study: NSIGHT-NC NEXUS
Accession: SCV001251460.1 First in ClinVar: May 31, 2020 Last updated: May 31, 2020
Comment:
carrier finding
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Comment:
The POLG c.1399G>A (p.A467T) variant is the most common POLG variant associated with autosomal recessive Alpers-Huttenlocher syndrome (characterized by seizures, loss of mental and movement … (more)
The POLG c.1399G>A (p.A467T) variant is the most common POLG variant associated with autosomal recessive Alpers-Huttenlocher syndrome (characterized by seizures, loss of mental and movement abilities, and liver disease PMID: 20301791). (less)
Number of individuals with the variant: 1
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Pathogenic
(May 07, 2019)
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criteria provided, single submitter
Method: clinical testing
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Mitochondrial DNA depletion syndrome 4b
Affected status: yes
Allele origin:
unknown
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Centre for Mendelian Genomics, University Medical Centre Ljubljana
Accession: SCV001368867.2
First in ClinVar: Jul 04, 2020 Last updated: Jul 04, 2020 |
Comment:
This variant was classified as: Pathogenic. The following ACMG criteria were applied in classifying this variant: PS1,PS3,PM2,PM3,PP3.
|
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Pathogenic
(Mar 26, 2020)
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criteria provided, single submitter
Method: clinical testing
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Progressive external ophthalmoplegia with mitochondrial DNA deletions, autosomal dominant 1
Affected status: yes
Allele origin:
unknown
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Baylor Genetics
Accession: SCV001522833.1
First in ClinVar: Mar 22, 2021 Last updated: Mar 22, 2021 |
Comment:
This variant was determined to be pathogenic according to ACMG Guidelines, 2015 [PMID:25741868]. Both variants have been previously reported as disease-causing [PMID 19578034 etc.]
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Pathogenic
(Nov 25, 2019)
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criteria provided, single submitter
Method: clinical testing
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Not Provided
Affected status: yes
Allele origin:
germline
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GeneDx
Accession: SCV000242281.11
First in ClinVar: Aug 07, 2015 Last updated: Apr 17, 2019 |
Comment:
Identified in individuals with autosomal recessive progressive external ophthalmoplegia (arPEO) and has subsequently been identified in patients with Alpers syndrome, sensory ataxic neuropathy dysarthria and … (more)
Identified in individuals with autosomal recessive progressive external ophthalmoplegia (arPEO) and has subsequently been identified in patients with Alpers syndrome, sensory ataxic neuropathy dysarthria and ophthalmoparesis (SANDO), and other POLG-related disorders causing epilepsy, ataxia, neuropathy, hepatopathy, and/or myopathy (vanGoethem et al., 2001); Published functional studies demonstrate a damaging effect (Kasahara et al., 2016); In silico analysis, which includes protein predictors and evolutionary conservation, supports a deleterious effect; This variant is associated with the following publications: (PMID: 22616202, 16368709, 11431686, 20837861, 21235791, 21686371, 22189570, 21515089, 22342071, 23448099, 22995991, 15917273, 21993618, 23212759, 18500570, 23430834, 24272679, 23783014, 20576279, 20691285, 20818383, 22931735, 22006280, 21647632, 25286830, 20138553, 21880868, 16024923, 26104464, 26735972, 27987238, 15122711, 15824347, 18783964, 19501198, 19766516, 28771251, 19813183, 19538466, 29588995, 18546343, 24725338, 29655203, 30167885, 30423451, 30369941, 27422324, 31980526, 31589614, 33473333) (less)
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Pathogenic
(Aug 23, 2021)
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criteria provided, single submitter
Method: clinical testing
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Progressive sclerosing poliodystrophy
Mitochondrial DNA depletion syndrome 4b Sensory ataxic neuropathy, dysarthria, and ophthalmoparesis Progressive external ophthalmoplegia with mitochondrial DNA deletions, autosomal recessive 1
Affected status: yes
Allele origin:
germline
|
Greenwood Genetic Center Diagnostic Laboratories, Greenwood Genetic Center
Accession: SCV002061523.2
First in ClinVar: Jan 22, 2022 Last updated: Feb 11, 2022 |
Comment:
PS3, PS4, PM1, PM3, PP3
|
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Pathogenic
(-)
|
criteria provided, single submitter
Method: clinical testing
|
Progressive sclerosing poliodystrophy
Affected status: yes
Allele origin:
maternal
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Equipe Genetique des Anomalies du Developpement, Université de Bourgogne
Accession: SCV001554492.2
First in ClinVar: Apr 13, 2021 Last updated: Mar 02, 2022 |
|
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Pathogenic
(Aug 29, 2022)
|
criteria provided, single submitter
Method: clinical testing
|
Progressive sclerosing poliodystrophy
Affected status: yes
Allele origin:
germline
|
MGZ Medical Genetics Center
Accession: SCV002581865.1
First in ClinVar: Oct 15, 2022 Last updated: Oct 15, 2022
Comment:
ACMG criteria applied: PS3, PM3_STR, PS4_MOD, PM2_SUP, PP3, PP4
|
Number of individuals with the variant: 7
Sex: female
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Pathogenic
(Dec 28, 2021)
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criteria provided, single submitter
Method: clinical testing
|
Progressive external ophthalmoplegia with mitochondrial DNA deletions, autosomal dominant 1
Progressive sclerosing poliodystrophy Progressive external ophthalmoplegia with mitochondrial DNA deletions, autosomal recessive 1 Mitochondrial DNA depletion syndrome 1 Sensory ataxic neuropathy, dysarthria, and ophthalmoparesis Mitochondrial DNA depletion syndrome 4b
Affected status: unknown
Allele origin:
unknown
|
Fulgent Genetics, Fulgent Genetics
Accession: SCV000611297.2
First in ClinVar: Nov 11, 2017 Last updated: Dec 31, 2022 |
|
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Pathogenic
(Dec 06, 2022)
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criteria provided, single submitter
Method: clinical testing
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POLG-Related Spectrum Disorders
Affected status: unknown
Allele origin:
germline
|
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Accession: SCV002819290.1
First in ClinVar: Jan 15, 2023 Last updated: Jan 15, 2023 |
Comment:
Variant summary: POLG c.1399G>A (p.Ala467Thr) results in a non-conservative amino acid change in the encoded protein sequence. Four of five in-silico tools predict a damaging … (more)
Variant summary: POLG c.1399G>A (p.Ala467Thr) results in a non-conservative amino acid change in the encoded protein sequence. Four of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 0.00051 in 251484 control chromosomes (gnomAD). c.1399G>A has been reported in the literature as a biallelic genotype in multiple individuals affected with POLG-Related Spectrum Disorders (e.g. Van Goethem_2003, Luoma_2005, Winterthun_2005, Kollberg_2006). These data indicate that the variant is very likely to be associated with disease. Functional analysis using purified recombinant protein showed the variant had reduced binding affinity to DNA and reduced DNA synthesis activity (14% and 18% of controls, respectively. Luoma_2005). Twenty-five ClinVar submitters have assessed the variant since 2014: all classified the variant as pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. (less)
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Pathogenic
(Aug 04, 2022)
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criteria provided, single submitter
Method: clinical testing
|
Sensory ataxic neuropathy, dysarthria, and ophthalmoparesis
Affected status: yes
Allele origin:
germline
|
Laboratorio de Genetica e Diagnostico Molecular, Hospital Israelita Albert Einstein
Accession: SCV003806775.1
First in ClinVar: Mar 04, 2023 Last updated: Mar 04, 2023 |
Comment:
ACMG classification criteria: PS4 strong, PM3 very strong, PP1 strong, PP3 supporting, PP4
Number of individuals with the variant: 1
Clinical Features:
Dysphagia (present) , Ptosis (present) , Truncal ataxia (present) , Cerebellar ataxia (present) , Ophthalmoparesis (present) , Seizure (present)
Geographic origin: Brazil
Method: Paired-end whole-genome sequencing
|
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Pathogenic
(Jul 22, 2020)
|
criteria provided, single submitter
Method: clinical testing
|
Progressive sclerosing poliodystrophy
Affected status: yes
Allele origin:
paternal
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Victorian Clinical Genetics Services, Murdoch Childrens Research Institute
Accession: SCV003921773.1
First in ClinVar: May 06, 2023 Last updated: May 06, 2023 |
Comment:
0102 - Loss of function is a known mechanism of disease in this gene and is associated with POLG-related mitochondrial disorders. (I) 0108 - This … (more)
0102 - Loss of function is a known mechanism of disease in this gene and is associated with POLG-related mitochondrial disorders. (I) 0108 - This gene is associated with both recessive and dominant disease. Variants in this gene predominantly cause recessive disease however, progressive external ophthalmoplegia can also be dominantly inherited (OMIM). (I) 0112 - Autosomal dominant progressive external ophthalmoplegia associated with this gene has incomplete penetrance (OMIM). (I) 0200 - Variant is predicted to result in a missense amino acid change from alanine to threonine. (I) 0251 - This variant is heterozygous. (I) 0304 - Variant is present in gnomAD <0.01 for a recessive condition (v2: 143 heterozygotes, 0 homozygotes). (SP) 0502 - Missense variant with conflicting in silico predictions and uninformative conservation. (I) 0600 - Variant is located in the linker region (PMID: 16024923). (I) 0801 - This variant has strong previous evidence of pathogenicity in unrelated individuals. This is one of the most reported variants predominantly in homozygous and compound heterozygous individuals with mitochondrial DNA depletion syndrome 4A (Alpers type) (ClinVar, PMID: 20301791). (SP) 1208 - Inheritance information for this variant is not currently available in this individual. (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign (less)
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Pathogenic
(Dec 13, 2022)
|
criteria provided, single submitter
Method: clinical testing
|
Progressive external ophthalmoplegia with mitochondrial DNA deletions, autosomal recessive 1
(Autosomal recessive inheritance)
Affected status: yes
Allele origin:
germline
|
Genetics and Molecular Pathology, SA Pathology
Additional submitter:
Shariant Australia, Australian Genomics
Accession: SCV004175638.1
First in ClinVar: Dec 17, 2023 Last updated: Dec 17, 2023 |
Comment:
The POLG gene encodes the alpha subunit of polymerase gamma, a mitochondrial DNA polymerase. Pathogenic variants in POLG have been assocaited with Mitochondrial DNA depletion … (more)
The POLG gene encodes the alpha subunit of polymerase gamma, a mitochondrial DNA polymerase. Pathogenic variants in POLG have been assocaited with Mitochondrial DNA depletion syndrome types 4A and 4B as well as autosomal dominant and recessive forms of Progressive external ophthalmoplegia (OMIM 174763). Variant Interpretation The POLG c.1399G>A missense variant is classified as PATHOGENIC (PS4, PM3, PS3, PP3) The POLG c.1399G>A missense variant is a single nucleotide change in exon 7 of the POLG gene, which is predicted to change the amino acid alanine at position 467 in the protein to threonine. This recurrent variant has been reported in both homozgous and compound heterozygous state in multiple patients with autosomal recessive progressive external ophthalmoplegia 1 (PMID: 11431686, 15824347) (PS4, PM3). Functional studies have demonstrated a significant reduction (96%) in gamma DNA polymerase enzyme activity in mutant cells compared with wild-type (PMID: 16024923) (PS3). This variant has been reported in dbSNP (rs113994095) and has been reported in population databases (gnomAD allele frequency = 0.048%, 143 het and 0 hom in 282888 sequenced alleles). this variant has been reported in ClinVar as pathogenic by multiple diagnostic laboratories (Variation ID: 13496). It has been reported as damaging for Progressive external ophthalmoplegia in the HGMD disease database (CM30938). Computational predictions support a deleterious effect on the gene or gene product (PP3). (less)
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Pathogenic
(Jul 07, 2022)
|
criteria provided, single submitter
Method: clinical testing
|
Not provided
Affected status: unknown
Allele origin:
germline
|
Mayo Clinic Laboratories, Mayo Clinic
Accession: SCV000802092.4
First in ClinVar: Aug 04, 2018 Last updated: Jan 26, 2024 |
Comment:
PP3, PM2, PM3, PS3, PS4_moderate
Number of individuals with the variant: 20
|
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Pathogenic
(Sep 07, 2022)
|
criteria provided, single submitter
Method: clinical testing
|
not provided
Affected status: unknown
Allele origin:
unknown
|
Athena Diagnostics
Accession: SCV000614701.3
First in ClinVar: Dec 19, 2017 Last updated: Jan 26, 2024 |
Comment:
The frequency of this variant in the general population is consistent with pathogenicity ((Genome Aggregation Database (gnomAD), Cambridge, MA (URL: http://gnomad.broadinstitute.org)). This variant has been … (more)
The frequency of this variant in the general population is consistent with pathogenicity ((Genome Aggregation Database (gnomAD), Cambridge, MA (URL: http://gnomad.broadinstitute.org)). This variant has been identified in multiple individuals with different autosomal recessive POLG-related disorders. Assessment of experimental evidence suggests this variant results in abnormal protein function. In an in vitro study, this variant abrogated polymerase activity, processivity, and exonuclease activity (PMID: 27987238). In multiple individuals, this variant has been seen with a single recessive pathogenic variant in the same gene, suggesting this variant may also be pathogenic. (less)
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Pathogenic
(Jul 17, 2023)
|
criteria provided, single submitter
Method: clinical testing
|
not provided
Affected status: unknown
Allele origin:
germline
|
Revvity Omics, Revvity
Accession: SCV002019460.3
First in ClinVar: Nov 29, 2021 Last updated: Feb 04, 2024 |
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Pathogenic
(Nov 03, 2023)
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criteria provided, single submitter
Method: clinical testing
|
not provided
Affected status: unknown
Allele origin:
germline
|
ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories
Accession: SCV004564949.1
First in ClinVar: Feb 20, 2024 Last updated: Feb 20, 2024 |
Comment:
The POLG c.1399G>A; p.Ala467Thr variant (rs113994095) is reported in association with recessive forms of disease. This variant is one of the most common pathogenic variants … (more)
The POLG c.1399G>A; p.Ala467Thr variant (rs113994095) is reported in association with recessive forms of disease. This variant is one of the most common pathogenic variants in POLG (Cohen 2018) and is reported in the literature in the homozygous or compound heterozygous state in numerous individuals affected with POLG-related disorders (Horvath 2006, Luoma 2005, Tzoulis 2006, Van Goethem 2001). This variant is also reported as pathogenic in ClinVar (Variation ID: 13496) and is found in the general population with an overall allele frequency of 0.05% (143/282,888 alleles) in the Genome Aggregation Database (v2.1.1). Computational analyses predict that this variant is deleterious (REVEL: 0.884). Functional studies of the variant protein suggest it has reduced affinity for DNA and has significantly decreased polymerase activity compared to wildtype POLG (Chan 2005, Luoma 2006). Based on available information, this variant is considered to be pathogenic. References: Chan SS et al. The common A467T mutation in the human mitochondrial DNA polymerase (POLG) compromises catalytic efficiency and interaction with the accessory subunit. J Biol Chem. 2005 Sep 9;280(36):31341-6. PMID: 16024923. Cohen BH et al. POLG-Related Disorders. GeneReviews. 2018. (https://www.ncbi.nlm.nih.gov/books/NBK26471/). PMID: 20301791. Horvath R et al. Phenotypic spectrum associated with mutations of the mitochondrial polymerase gamma gene. Brain. 2006 Jul;129(Pt 7):1674-84. PMID: 16621917. Luoma PT et al. Functional defects due to spacer-region mutations of human mitochondrial DNA polymerase in a family with an ataxia-myopathy syndrome. Hum Mol Genet. 2005 Jul 15;14(14):1907-20. PMID: 15917273. Tzoulis C et al. The spectrum of clinical disease caused by the A467T and W748S POLG mutations: a study of 26 cases. Brain. 2006 Jul;129(Pt 7):1685-92. PMID: 16638794. Van Goethem G et al. Mutation of POLG is associated with progressive external ophthalmoplegia characterized by mtDNA deletions. Nat Genet. 2001 Jul;28(3):211-2. PMID: 11431686. (less)
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Pathogenic
(Jan 29, 2024)
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criteria provided, single submitter
Method: clinical testing
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Progressive sclerosing poliodystrophy
Affected status: unknown
Allele origin:
germline
|
Labcorp Genetics (formerly Invitae), Labcorp
Accession: SCV000630094.9
First in ClinVar: Dec 26, 2017 Last updated: Feb 28, 2024 |
Comment:
This sequence change replaces alanine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 467 of the POLG protein (p.Ala467Thr). … (more)
This sequence change replaces alanine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 467 of the POLG protein (p.Ala467Thr). This variant is present in population databases (rs113994095, gnomAD 0.09%), and has an allele count higher than expected for a pathogenic variant. This missense change has been observed in individual(s) with autosomal recessive POLG-related disorders, Alpers-Huttenlocher syndrome, autosomal recessive progressive external ophthalmoplegia, sensory ataxic neuropathy, dysarthria and ophthalmoplegia (SANDO), and other POLG-related disorders causing epilepsy, ataxia, neuropathy, hepatopathy, and myopathy (PMID: 11431686, 15122711, 15917273, 20691285, 25286830, 26735972). It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 13496). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) has been performed at Invitae for this missense variant, however the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on POLG protein function. Experimental studies have shown that this missense change affects POLG function (PMID: 15917273, 16024923). For these reasons, this variant has been classified as Pathogenic. (less)
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Pathogenic
(Mar 30, 2023)
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criteria provided, single submitter
Method: clinical testing
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Progressive external ophthalmoplegia with mitochondrial DNA deletions, autosomal recessive 1
Affected status: yes
Allele origin:
germline
|
Molecular Genetics, Royal Melbourne Hospital
Additional submitter:
Shariant Australia, Australian Genomics
Accession: SCV002503861.2
First in ClinVar: Apr 23, 2022 Last updated: Apr 15, 2024 |
Comment:
This sequence change is predicted to replace alanine with threonine at codon 467 of the POLG protein (p.Ala467Thr). The alanine residue is highly conserved (100 … (more)
This sequence change is predicted to replace alanine with threonine at codon 467 of the POLG protein (p.Ala467Thr). The alanine residue is highly conserved (100 vertebrates, UCSC), and is located in a helix within the linker region. There is a small physicochemical difference between alanine and threonine. The variant is present in a large population cohort at a frequency of 0.051%] (rs113994095, 143/282,888 alleles, 0 homozygotes in gnomAD v2.1). The variant is the most commonly reported POLG variant. It has been identified in the homozygous state and compound heterozygous with a second pathogenic allele in various POLG-related disorders, and segregates with disease in multiple families (PMID: 11431686, 15122711, 15917273, 21880868 - PM3_VeryStrong, PP1_Moderate). In vitro assays show reduced enzyme activity and DNA binding for the variant (PMID: 15917273, 16024923 - PS3_Supporting). Multiple lines of computational evidence predict a deleterious effect for the missense substitution (6/7 algorithms - PP3). Based on the classification scheme RMH ACMG Guidelines v1.2.1, this variant is classified as PATHOGENIC. Following criteria are met: PM3_VeryStrong, PP1_Moderate, PS3_Supporting, PP3. (less)
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Pathogenic
(Mar 27, 2024)
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criteria provided, single submitter
Method: clinical testing
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Progressive sclerosing poliodystrophy
Affected status: unknown
Allele origin:
unknown
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Baylor Genetics
Accession: SCV004205837.2
First in ClinVar: Dec 30, 2023 Last updated: Jun 17, 2024 |
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Pathogenic
(Oct 01, 2018)
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criteria provided, single submitter
Method: clinical testing
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Progressive sclerosing poliodystrophy
Affected status: unknown
Allele origin:
germline
|
Wong Mito Lab, Molecular and Human Genetics, Baylor College of Medicine
Accession: SCV000886901.1
First in ClinVar: Dec 15, 2018 Last updated: Dec 15, 2018 |
Comment:
The NM_002693.2:c.1399G>A (NP_002684.1:p.Ala467Thr) [GRCH38: NC_000015.10:g.89327201C>T] variant in POLG gene is interpretated to be a Pathogenic based on ACMG guidelines (PMID: 25741868). This variant meets the … (more)
The NM_002693.2:c.1399G>A (NP_002684.1:p.Ala467Thr) [GRCH38: NC_000015.10:g.89327201C>T] variant in POLG gene is interpretated to be a Pathogenic based on ACMG guidelines (PMID: 25741868). This variant meets the following evidence codes reported in the ACMG-guideline. PS3:Well established functional studies show a deleterious effect on POLG. PS4:Prevalence of variant in affecteds statistically increased over controls. PM3:Detected in trans with a pathogenic variant for Mitochondrial DNA depletion syndrome 4A (Alpers type) which is a recessive disorder. PP1:This variant is co-segregated with Mitochondrial DNA depletion syndrome 4A (Alpers type) in multiple affected family members. PP4:Patient's phenotype or family history is highly specific for POLG. PP5:Reputable source(s) suggest that the variant is pathogenic. Based on the evidence criteria codes applied, the variant is suggested to be Pathogenic. (less)
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Pathogenic
(Nov 08, 2018)
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criteria provided, single submitter
Method: clinical testing
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Sensory ataxic neuropathy, dysarthria, and ophthalmoparesis
(Autosomal recessive inheritance)
Affected status: yes
Allele origin:
paternal,
maternal
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Institute of Human Genetics Munich, Klinikum Rechts Der Isar, TU München
Accession: SCV001150219.1
First in ClinVar: Feb 03, 2020 Last updated: Feb 03, 2020 |
Observation 1:
Sex: female
Tissue: blood
Observation 2:
Sex: female
Tissue: blood
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Pathogenic
(Oct 23, 2020)
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criteria provided, single submitter
Method: clinical testing
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not provided
(Unknown mechanism)
Affected status: yes
Allele origin:
germline
|
Institute of Medical Genetics and Applied Genomics, University Hospital Tübingen
Accession: SCV001447214.1
First in ClinVar: Nov 28, 2020 Last updated: Nov 28, 2020 |
Clinical Features:
Cerebellar ataxia (present) , Motor delay (present) , Elevated circulating creatinine concentration (present) , Short stature (present)
Sex: male
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Pathogenic
(Jul 21, 2020)
|
criteria provided, single submitter
Method: clinical testing
|
Progressive sclerosing poliodystrophy
Mitochondrial DNA depletion syndrome 4b Sensory ataxic neuropathy, dysarthria, and ophthalmoparesis Progressive external ophthalmoplegia with mitochondrial DNA deletions, autosomal recessive 1 Progressive external ophthalmoplegia with mitochondrial DNA deletions, autosomal dominant 1
Affected status: yes
Allele origin:
germline
|
Rady Children's Institute for Genomic Medicine, Rady Children's Hospital San Diego
Accession: SCV001984827.1
First in ClinVar: Oct 30, 2021 Last updated: Oct 30, 2021 |
Comment:
This variant has been previously reported as a homozygous and a compound heterozygous change in multiple patients and reported to segregate in several families affected … (more)
This variant has been previously reported as a homozygous and a compound heterozygous change in multiple patients and reported to segregate in several families affected by autosomal recessive POLG-related disorders including Alpers-Huttenlocher syndrome (AHS), progressive ataxic neuropathy, Parieto-occipital lobe epilepsy and Mitochondrial neurogastrointestinal encephalomyopathy-like syndrome (PMID: 11431686, 26735972, 15122711, 25286830, 20691285, 15917273). This is the most common AHS-causing variant in the POLG gene. Functional characterization indicates that the p.Ala467Thr variant, which is located near the exonuclease domain in the early linker region of the protein, severely reduces DNA polymerase gamma activity (down to 4% of wild type activity) by compromising the catalytic efficiency of the POLG protein (PMID: 16024923, 15917273). In addition, p.Ala467Thr fails to associate with the POLG2 accessory subunit, which leads to stalling at the replication fork and depletion of mtDNA over time (PMID: 16024923, 27987238, 16368709). The p.Ala467Thr variant is present in the heterozygous state in the gnomAD population database at a frequency of 0.051% (143/282888) and thus is presumed to be rare. In silico analyses support a deleterious effect of the c.1399G>A (p.Ala467Thr) variant on protein function. Based on the available evidence, the c.1399G>A (p.Ala467Thr) variant is classified as Pathogenic. (less)
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Pathogenic
(May 01, 2020)
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criteria provided, single submitter
Method: clinical testing
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Hereditary spastic paraplegia
Affected status: yes
Allele origin:
germline
|
Genome Diagnostics Laboratory, The Hospital for Sick Children
Accession: SCV002105549.1
First in ClinVar: Mar 19, 2022 Last updated: Mar 19, 2022 |
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Pathogenic
(Mar 17, 2022)
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criteria provided, single submitter
Method: clinical testing
|
Not provided
Affected status: yes
Allele origin:
germline
|
AiLife Diagnostics, AiLife Diagnostics
Accession: SCV002502115.1
First in ClinVar: Apr 23, 2022 Last updated: Apr 23, 2022 |
Number of individuals with the variant: 2
Secondary finding: no
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Pathogenic
(-)
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criteria provided, single submitter
Method: clinical testing
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Neurodevelopmental delay
Affected status: yes
Allele origin:
biparental
|
Centre de Biologie Pathologie Génétique, Centre Hospitalier Universitaire de Lille
Accession: SCV002559145.1
First in ClinVar: Aug 15, 2022 Last updated: Aug 15, 2022 |
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Pathogenic
(Oct 22, 2021)
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criteria provided, single submitter
Method: clinical testing
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Inborn genetic diseases
Affected status: unknown
Allele origin:
germline
|
Ambry Genetics
Accession: SCV000851036.4
First in ClinVar: Nov 08, 2018 Last updated: May 01, 2024 |
Comment:
The c.1399G>A (p.A467T) alteration is located in exon 7 (coding exon 6) of the POLG gene. This alteration results from a G to A substitution … (more)
The c.1399G>A (p.A467T) alteration is located in exon 7 (coding exon 6) of the POLG gene. This alteration results from a G to A substitution at nucleotide position 1399, causing the alanine (A) at amino acid position 467 to be replaced by a threonine (T). Based on the available evidence, this alteration is classified as pathogenic for autosomal recessive POLG-related mitochondrial disorders; however, the association of this alteration with autosomal dominant progressive external ophthalmoplegia is unlikely. Based on data from gnomAD, the A allele has an overall frequency of 0.05% (143/282888) total alleles studied. The highest observed frequency was 0.1% (127/129190) of European (non-Finnish) alleles. This mutation is the most common recessive pathogenic mutation found in POLG and accounts for 31% of all mutant alleles (Tang, 2011). This mutation has been identified in both compound heterozygous and homozygous states in many individuals presenting with a wide range of mitochondrial disorders, including but not limited to: Alpers syndrome, juvenile spinocerebellar ataxia-epilepsy syndrome, progressive external ophthalmoplegia, and other POLG-related disorders including ataxia, neuropathy, epilepsy, hepatopathy, and myopathy (Chan, 2005; Tang, 2011; Van Goethem, 2001; Van Goethem, 2004; Luoma, 2005; Janssen, 2016; Rajakulendran, 2016). This amino acid position is highly conserved in available vertebrate species. In vitro functional studies demonstrate that the p.A467T mutation results in 4-20% of wild-type DNA polymerase activity and fails to interact with the catalytic accessory subunit resulting in compromised catalytic activity (Chan, 2005). This alteration is predicted to be deleterious by in silico analysis. Based on the available evidence, this alteration is classified as pathogenic. (less)
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Pathogenic
(Nov 08, 2018)
|
criteria provided, single submitter
Method: clinical testing
|
Tip-toe gait
Affected status: yes
Allele origin:
unknown
|
Practice for Gait Abnormalities, David Pomarino, Competency Network Toe Walking c/o Practice Pomarino
Accession: SCV001573093.2
First in ClinVar: May 10, 2021 Last updated: Jun 09, 2024 |
Comment:
Hereditary motor sensory neuropathy (HMSN), also known as Charcot-Marie-Tooth Disease (CMT), is the most commonly inherited peripheral polyneuropathy. It constitutes a group of inherited, progressive, … (more)
Hereditary motor sensory neuropathy (HMSN), also known as Charcot-Marie-Tooth Disease (CMT), is the most commonly inherited peripheral polyneuropathy. It constitutes a group of inherited, progressive, motor and sensory peripheral nerve disorders with properties of demyelination, axonal degeneration, or both. It is classified by clinical characteristics, modes of inheritance, electrophysiologic features, metabolic defects, and specific gene markers. Our patients all walk on tiptoe, so they show similar symptoms. When we genetically test them with our toe walking panel, we find that around 90 per cent of them have a genetic variant that explains their toe walking. These can be assigned, for example, to the area of myopathies (such as variants of the COL6A3 gene), the area of hereditary neuropathies (such as variants of the KMT2C gene) or the area of metabolic diseases (such as variants of the PYGM gene). In a smaller group of patients with almost identical symptoms, no abnormality is found in the genes of our panel, but spastic paraplegia can be detected. In another small group of our toe walkers, no abnormalities can be detected in the genes analysed in our toe walking panel, nor do they suffer from spastic paraplegia, as is also the case with healthy children. In contrast to these, however, they show a tiptoe gait. These patients suffer from infantile cerebral palsy, in which toe walking can also be observed. (less)
Clinical Features:
Pes cavus (present) , limited range of motion of the upper ankle (present)
Age: 10-19 years
Sex: male
Method: Gene panel analysis
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Pathogenic
(Dec 07, 2023)
|
criteria provided, single submitter
Method: clinical testing
|
not provided
Affected status: yes
Allele origin:
germline
|
Clinical Genetics Laboratory, Skane University Hospital Lund
Accession: SCV005197250.1
First in ClinVar: Aug 25, 2024 Last updated: Aug 25, 2024 |
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Pathogenic
(Mar 01, 2024)
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criteria provided, single submitter
Method: clinical testing
|
not provided
Affected status: yes
Allele origin:
germline
|
CeGaT Center for Human Genetics Tuebingen
Accession: SCV000493450.31
First in ClinVar: Oct 09, 2016 Last updated: Oct 20, 2024 |
Comment:
POLG: PM3:Very Strong, PP1:Strong, PS3, PM2
Number of individuals with the variant: 32
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Pathogenic
(Feb 11, 2011)
|
no assertion criteria provided
Method: literature only
|
MITOCHONDRIAL DNA DEPLETION SYNDROME 4A (ALPERS TYPE)
Affected status: not provided
Allele origin:
germline
|
OMIM
Accession: SCV000034693.4
First in ClinVar: Apr 04, 2013 Last updated: Oct 14, 2016 |
Comment on evidence:
In a family with 3 affected sibs with autosomal recessive PEO (PEOB1; 258450), Van Goethem et al. (2001) identified compound heterozygosity for 2 missense mutations … (more)
In a family with 3 affected sibs with autosomal recessive PEO (PEOB1; 258450), Van Goethem et al. (2001) identified compound heterozygosity for 2 missense mutations in the POLG gene: a 1399G-A transition, resulting in an ala467-to-thr (A467T) substitution, and a 911T-G transversion, resulting in a leu304-to-arg substitution (L304R; 174763.0003). In 2 affected individuals in another family, Van Goethem et al. (2001) identified the A467T mutation in compound heterozygous state with an 8G-C transversion, resulting in an arg3-to-pro substitution (R3P; 174763.0004). Three of 229 control individuals were heterozygous for A467T (allele T frequency of 0.6%). The R3P mutation was not observed in any of the control individuals. The A467T mutation occurs in the linker region of the protein (Stewart et al., 2009). Van Goethem et al. (2003) stated that the A467T mutation has a frequency of 0.6% in the Belgian population and that sensory neuropathy is the initial feature in Belgian compound heterozygous autosomal recessive progressive external ophthalmoplegia patients, all carrying the POLG A467T mutation in combination with another mutation. Van Goethem et al. (2003) reported a patient who was homozygous for the A467T mutation, which they incorrectly reported as ALA476THR. (Van Broeckhoven (2004) reported the correct mutation as A467T.) At age 15 years, the patient experienced mild ataxia, and later developed myoclonus, seizures, and sensory neuropathy. External ophthalmoplegia was absent on repeated examinations. Muscle biopsy did not show any abnormalities, including no ragged-red fibers, but long-range PCR detected a low proportion of mtDNA deletions in the patient's muscle. Van Goethem et al. (2003) noted that the clinical features in this patient were unique and suggested that some features overlapped with the syndrome of myoclonus, epilepsy, and ragged-red fibers (MERRF; 545000). In 3 sibs with sensory ataxic neuropathy, dysarthria, and ophthalmoparesis (607459) originally reported by Rantamaki et al. (2001), Van Goethem et al. (2004) identified homozygosity for the A467T mutation. An unrelated British patient was compound heterozygous for the A467T mutation and W748S (174763.0013). An unrelated Belgian patient with a variant form of SANDO without ophthalmoparesis was also homozygous for the A467T mutation. That patient had psychiatric symptoms, severe gastroparesis, and dilated cardiomyopathy, illustrating the variable clinical phenotype that can result from recessive POLG mutations. In 2 affected patients from a family with mitochondrial DNA depletion syndrome-4A (MTDPS4A; 203700), manifest as Alpers syndrome, Naviaux and Nguyen (2005) identified compound heterozygosity for 2 mutations in the POLG gene: A467T and E873X (174763.0008). An earlier report on these patients by Naviaux and Nguyen (2004) had incorrectly stated that they were homozygous for the E873X mutation. In 2 sisters with mtDNA depletion syndrome manifest as Alpers syndrome, Nguyen et al. (2005) identified compound heterozygosity for 2 mutations in the POLG gene: a A467T and W1020X (174763.0017). Two affected sibs from another family with Alpers syndrome were compound heterozygous for A467T and G848S (174763.0006). Another child with Alpers syndrome from an unrelated family who was homozygous for the A467T mutation showed late-onset at age 8.5 years and death by age 9 years. Winterthun et al. (2005) identified homozygosity for the A467T mutation in affected members from 2 families with a form of SANDO characterized by early onset of migraine headaches and/or seizures, and the later development of myoclonus (see SCAE; 607459). Hakonen et al. (2007) demonstrated that the A467T disease chromosomes of patients from Australia, New Zealand, and the United States shared a common haplotype with European patients, indicating that they all derived from a common European founder. Further analysis indicated that the Norwegian A467T disease haplotype diverged from the European founder earlier than the other haplotypes. Hakonen et al. (2007) estimated that the common ancestor for A467T lived more than 15 to 30 generations ago, before 1700 to 1400 A.D. By reevaluation of 2 sibs reported by Bird and Shaw (1978), who were classified as having progressive myoclonic epilepsy-5 (EPM5; see 607459), Sandford et al. (2016) identified compound heterozygous mutations in the POLG gene (A467T on 1 allele and W748S, 174763.0013 and G497H, 174763.0016 in cis on the other allele). In these sibs, Tao et al. (2011) had previously identified 2 heterozygous missense variants in the PRICKLE2 gene (608501.0001) that occurred on the same allele. Furthermore, Sandford et al. (2016) showed that the 2 heterozygous missense variants in the PRICKLE2 gene identified by Tao et al. (2011) occurred on opposite chromosomes, which would be more consistent with recessive inheritance. Sandford et al. (2016) concluded that the phenotype in these patients resulted from the POLG mutations and not from the PRICKLE2 variants. In a response, Mahajan and Bassuk (2016) maintained that the PRICKLE2 variants identified by Tao et al. (2011) contributed to the phenotype in their patients. (less)
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Pathogenic
(Feb 11, 2011)
|
no assertion criteria provided
Method: literature only
|
SPINOCEREBELLAR ATAXIA WITH EPILEPSY
Affected status: not provided
Allele origin:
germline
|
OMIM
Accession: SCV000034692.4
First in ClinVar: Apr 04, 2013 Last updated: Oct 14, 2016 |
Comment on evidence:
In a family with 3 affected sibs with autosomal recessive PEO (PEOB1; 258450), Van Goethem et al. (2001) identified compound heterozygosity for 2 missense mutations … (more)
In a family with 3 affected sibs with autosomal recessive PEO (PEOB1; 258450), Van Goethem et al. (2001) identified compound heterozygosity for 2 missense mutations in the POLG gene: a 1399G-A transition, resulting in an ala467-to-thr (A467T) substitution, and a 911T-G transversion, resulting in a leu304-to-arg substitution (L304R; 174763.0003). In 2 affected individuals in another family, Van Goethem et al. (2001) identified the A467T mutation in compound heterozygous state with an 8G-C transversion, resulting in an arg3-to-pro substitution (R3P; 174763.0004). Three of 229 control individuals were heterozygous for A467T (allele T frequency of 0.6%). The R3P mutation was not observed in any of the control individuals. The A467T mutation occurs in the linker region of the protein (Stewart et al., 2009). Van Goethem et al. (2003) stated that the A467T mutation has a frequency of 0.6% in the Belgian population and that sensory neuropathy is the initial feature in Belgian compound heterozygous autosomal recessive progressive external ophthalmoplegia patients, all carrying the POLG A467T mutation in combination with another mutation. Van Goethem et al. (2003) reported a patient who was homozygous for the A467T mutation, which they incorrectly reported as ALA476THR. (Van Broeckhoven (2004) reported the correct mutation as A467T.) At age 15 years, the patient experienced mild ataxia, and later developed myoclonus, seizures, and sensory neuropathy. External ophthalmoplegia was absent on repeated examinations. Muscle biopsy did not show any abnormalities, including no ragged-red fibers, but long-range PCR detected a low proportion of mtDNA deletions in the patient's muscle. Van Goethem et al. (2003) noted that the clinical features in this patient were unique and suggested that some features overlapped with the syndrome of myoclonus, epilepsy, and ragged-red fibers (MERRF; 545000). In 3 sibs with sensory ataxic neuropathy, dysarthria, and ophthalmoparesis (607459) originally reported by Rantamaki et al. (2001), Van Goethem et al. (2004) identified homozygosity for the A467T mutation. An unrelated British patient was compound heterozygous for the A467T mutation and W748S (174763.0013). An unrelated Belgian patient with a variant form of SANDO without ophthalmoparesis was also homozygous for the A467T mutation. That patient had psychiatric symptoms, severe gastroparesis, and dilated cardiomyopathy, illustrating the variable clinical phenotype that can result from recessive POLG mutations. In 2 affected patients from a family with mitochondrial DNA depletion syndrome-4A (MTDPS4A; 203700), manifest as Alpers syndrome, Naviaux and Nguyen (2005) identified compound heterozygosity for 2 mutations in the POLG gene: A467T and E873X (174763.0008). An earlier report on these patients by Naviaux and Nguyen (2004) had incorrectly stated that they were homozygous for the E873X mutation. In 2 sisters with mtDNA depletion syndrome manifest as Alpers syndrome, Nguyen et al. (2005) identified compound heterozygosity for 2 mutations in the POLG gene: a A467T and W1020X (174763.0017). Two affected sibs from another family with Alpers syndrome were compound heterozygous for A467T and G848S (174763.0006). Another child with Alpers syndrome from an unrelated family who was homozygous for the A467T mutation showed late-onset at age 8.5 years and death by age 9 years. Winterthun et al. (2005) identified homozygosity for the A467T mutation in affected members from 2 families with a form of SANDO characterized by early onset of migraine headaches and/or seizures, and the later development of myoclonus (see SCAE; 607459). Hakonen et al. (2007) demonstrated that the A467T disease chromosomes of patients from Australia, New Zealand, and the United States shared a common haplotype with European patients, indicating that they all derived from a common European founder. Further analysis indicated that the Norwegian A467T disease haplotype diverged from the European founder earlier than the other haplotypes. Hakonen et al. (2007) estimated that the common ancestor for A467T lived more than 15 to 30 generations ago, before 1700 to 1400 A.D. By reevaluation of 2 sibs reported by Bird and Shaw (1978), who were classified as having progressive myoclonic epilepsy-5 (EPM5; see 607459), Sandford et al. (2016) identified compound heterozygous mutations in the POLG gene (A467T on 1 allele and W748S, 174763.0013 and G497H, 174763.0016 in cis on the other allele). In these sibs, Tao et al. (2011) had previously identified 2 heterozygous missense variants in the PRICKLE2 gene (608501.0001) that occurred on the same allele. Furthermore, Sandford et al. (2016) showed that the 2 heterozygous missense variants in the PRICKLE2 gene identified by Tao et al. (2011) occurred on opposite chromosomes, which would be more consistent with recessive inheritance. Sandford et al. (2016) concluded that the phenotype in these patients resulted from the POLG mutations and not from the PRICKLE2 variants. In a response, Mahajan and Bassuk (2016) maintained that the PRICKLE2 variants identified by Tao et al. (2011) contributed to the phenotype in their patients. (less)
|
|
Pathogenic
(Feb 11, 2011)
|
no assertion criteria provided
Method: literature only
|
SENSORY ATAXIC NEUROPATHY, DYSARTHRIA, AND OPHTHALMOPARESIS
Affected status: not provided
Allele origin:
germline
|
OMIM
Accession: SCV000034691.4
First in ClinVar: Apr 04, 2013 Last updated: Oct 14, 2016 |
Comment on evidence:
In a family with 3 affected sibs with autosomal recessive PEO (PEOB1; 258450), Van Goethem et al. (2001) identified compound heterozygosity for 2 missense mutations … (more)
In a family with 3 affected sibs with autosomal recessive PEO (PEOB1; 258450), Van Goethem et al. (2001) identified compound heterozygosity for 2 missense mutations in the POLG gene: a 1399G-A transition, resulting in an ala467-to-thr (A467T) substitution, and a 911T-G transversion, resulting in a leu304-to-arg substitution (L304R; 174763.0003). In 2 affected individuals in another family, Van Goethem et al. (2001) identified the A467T mutation in compound heterozygous state with an 8G-C transversion, resulting in an arg3-to-pro substitution (R3P; 174763.0004). Three of 229 control individuals were heterozygous for A467T (allele T frequency of 0.6%). The R3P mutation was not observed in any of the control individuals. The A467T mutation occurs in the linker region of the protein (Stewart et al., 2009). Van Goethem et al. (2003) stated that the A467T mutation has a frequency of 0.6% in the Belgian population and that sensory neuropathy is the initial feature in Belgian compound heterozygous autosomal recessive progressive external ophthalmoplegia patients, all carrying the POLG A467T mutation in combination with another mutation. Van Goethem et al. (2003) reported a patient who was homozygous for the A467T mutation, which they incorrectly reported as ALA476THR. (Van Broeckhoven (2004) reported the correct mutation as A467T.) At age 15 years, the patient experienced mild ataxia, and later developed myoclonus, seizures, and sensory neuropathy. External ophthalmoplegia was absent on repeated examinations. Muscle biopsy did not show any abnormalities, including no ragged-red fibers, but long-range PCR detected a low proportion of mtDNA deletions in the patient's muscle. Van Goethem et al. (2003) noted that the clinical features in this patient were unique and suggested that some features overlapped with the syndrome of myoclonus, epilepsy, and ragged-red fibers (MERRF; 545000). In 3 sibs with sensory ataxic neuropathy, dysarthria, and ophthalmoparesis (607459) originally reported by Rantamaki et al. (2001), Van Goethem et al. (2004) identified homozygosity for the A467T mutation. An unrelated British patient was compound heterozygous for the A467T mutation and W748S (174763.0013). An unrelated Belgian patient with a variant form of SANDO without ophthalmoparesis was also homozygous for the A467T mutation. That patient had psychiatric symptoms, severe gastroparesis, and dilated cardiomyopathy, illustrating the variable clinical phenotype that can result from recessive POLG mutations. In 2 affected patients from a family with mitochondrial DNA depletion syndrome-4A (MTDPS4A; 203700), manifest as Alpers syndrome, Naviaux and Nguyen (2005) identified compound heterozygosity for 2 mutations in the POLG gene: A467T and E873X (174763.0008). An earlier report on these patients by Naviaux and Nguyen (2004) had incorrectly stated that they were homozygous for the E873X mutation. In 2 sisters with mtDNA depletion syndrome manifest as Alpers syndrome, Nguyen et al. (2005) identified compound heterozygosity for 2 mutations in the POLG gene: a A467T and W1020X (174763.0017). Two affected sibs from another family with Alpers syndrome were compound heterozygous for A467T and G848S (174763.0006). Another child with Alpers syndrome from an unrelated family who was homozygous for the A467T mutation showed late-onset at age 8.5 years and death by age 9 years. Winterthun et al. (2005) identified homozygosity for the A467T mutation in affected members from 2 families with a form of SANDO characterized by early onset of migraine headaches and/or seizures, and the later development of myoclonus (see SCAE; 607459). Hakonen et al. (2007) demonstrated that the A467T disease chromosomes of patients from Australia, New Zealand, and the United States shared a common haplotype with European patients, indicating that they all derived from a common European founder. Further analysis indicated that the Norwegian A467T disease haplotype diverged from the European founder earlier than the other haplotypes. Hakonen et al. (2007) estimated that the common ancestor for A467T lived more than 15 to 30 generations ago, before 1700 to 1400 A.D. By reevaluation of 2 sibs reported by Bird and Shaw (1978), who were classified as having progressive myoclonic epilepsy-5 (EPM5; see 607459), Sandford et al. (2016) identified compound heterozygous mutations in the POLG gene (A467T on 1 allele and W748S, 174763.0013 and G497H, 174763.0016 in cis on the other allele). In these sibs, Tao et al. (2011) had previously identified 2 heterozygous missense variants in the PRICKLE2 gene (608501.0001) that occurred on the same allele. Furthermore, Sandford et al. (2016) showed that the 2 heterozygous missense variants in the PRICKLE2 gene identified by Tao et al. (2011) occurred on opposite chromosomes, which would be more consistent with recessive inheritance. Sandford et al. (2016) concluded that the phenotype in these patients resulted from the POLG mutations and not from the PRICKLE2 variants. In a response, Mahajan and Bassuk (2016) maintained that the PRICKLE2 variants identified by Tao et al. (2011) contributed to the phenotype in their patients. (less)
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Pathogenic
(Feb 11, 2011)
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no assertion criteria provided
Method: literature only
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PROGRESSIVE EXTERNAL OPHTHALMOPLEGIA WITH MITOCHONDRIAL DNA DELETIONS, AUTOSOMAL RECESSIVE 1
Affected status: not provided
Allele origin:
germline
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OMIM
Accession: SCV000034690.4
First in ClinVar: Apr 04, 2013 Last updated: Mar 26, 2016 |
Comment on evidence:
In a family with 3 affected sibs with autosomal recessive PEO (PEOB1; 258450), Van Goethem et al. (2001) identified compound heterozygosity for 2 missense mutations … (more)
In a family with 3 affected sibs with autosomal recessive PEO (PEOB1; 258450), Van Goethem et al. (2001) identified compound heterozygosity for 2 missense mutations in the POLG gene: a 1399G-A transition, resulting in an ala467-to-thr (A467T) substitution, and a 911T-G transversion, resulting in a leu304-to-arg substitution (L304R; 174763.0003). In 2 affected individuals in another family, Van Goethem et al. (2001) identified the A467T mutation in compound heterozygous state with an 8G-C transversion, resulting in an arg3-to-pro substitution (R3P; 174763.0004). Three of 229 control individuals were heterozygous for A467T (allele T frequency of 0.6%). The R3P mutation was not observed in any of the control individuals. The A467T mutation occurs in the linker region of the protein (Stewart et al., 2009). Van Goethem et al. (2003) stated that the A467T mutation has a frequency of 0.6% in the Belgian population and that sensory neuropathy is the initial feature in Belgian compound heterozygous autosomal recessive progressive external ophthalmoplegia patients, all carrying the POLG A467T mutation in combination with another mutation. Van Goethem et al. (2003) reported a patient who was homozygous for the A467T mutation, which they incorrectly reported as ALA476THR. (Van Broeckhoven (2004) reported the correct mutation as A467T.) At age 15 years, the patient experienced mild ataxia, and later developed myoclonus, seizures, and sensory neuropathy. External ophthalmoplegia was absent on repeated examinations. Muscle biopsy did not show any abnormalities, including no ragged-red fibers, but long-range PCR detected a low proportion of mtDNA deletions in the patient's muscle. Van Goethem et al. (2003) noted that the clinical features in this patient were unique and suggested that some features overlapped with the syndrome of myoclonus, epilepsy, and ragged-red fibers (MERRF; 545000). In 3 sibs with sensory ataxic neuropathy, dysarthria, and ophthalmoparesis (607459) originally reported by Rantamaki et al. (2001), Van Goethem et al. (2004) identified homozygosity for the A467T mutation. An unrelated British patient was compound heterozygous for the A467T mutation and W748S (174763.0013). An unrelated Belgian patient with a variant form of SANDO without ophthalmoparesis was also homozygous for the A467T mutation. That patient had psychiatric symptoms, severe gastroparesis, and dilated cardiomyopathy, illustrating the variable clinical phenotype that can result from recessive POLG mutations. In 2 affected patients from a family with mitochondrial DNA depletion syndrome-4A (MTDPS4A; 203700), manifest as Alpers syndrome, Naviaux and Nguyen (2005) identified compound heterozygosity for 2 mutations in the POLG gene: A467T and E873X (174763.0008). An earlier report on these patients by Naviaux and Nguyen (2004) had incorrectly stated that they were homozygous for the E873X mutation. In 2 sisters with mtDNA depletion syndrome manifest as Alpers syndrome, Nguyen et al. (2005) identified compound heterozygosity for 2 mutations in the POLG gene: a A467T and W1020X (174763.0017). Two affected sibs from another family with Alpers syndrome were compound heterozygous for A467T and G848S (174763.0006). Another child with Alpers syndrome from an unrelated family who was homozygous for the A467T mutation showed late-onset at age 8.5 years and death by age 9 years. Winterthun et al. (2005) identified homozygosity for the A467T mutation in affected members from 2 families with a form of SANDO characterized by early onset of migraine headaches and/or seizures, and the later development of myoclonus (see SCAE; 607459). Hakonen et al. (2007) demonstrated that the A467T disease chromosomes of patients from Australia, New Zealand, and the United States shared a common haplotype with European patients, indicating that they all derived from a common European founder. Further analysis indicated that the Norwegian A467T disease haplotype diverged from the European founder earlier than the other haplotypes. Hakonen et al. (2007) estimated that the common ancestor for A467T lived more than 15 to 30 generations ago, before 1700 to 1400 A.D. By reevaluation of 2 sibs reported by Bird and Shaw (1978), who were classified as having progressive myoclonic epilepsy-5 (EPM5; see 607459), Sandford et al. (2016) identified compound heterozygous mutations in the POLG gene (A467T on 1 allele and W748S, 174763.0013 and G497H, 174763.0016 in cis on the other allele). In these sibs, Tao et al. (2011) had previously identified 2 heterozygous missense variants in the PRICKLE2 gene (608501.0001) that occurred on the same allele. Furthermore, Sandford et al. (2016) showed that the 2 heterozygous missense variants in the PRICKLE2 gene identified by Tao et al. (2011) occurred on opposite chromosomes, which would be more consistent with recessive inheritance. Sandford et al. (2016) concluded that the phenotype in these patients resulted from the POLG mutations and not from the PRICKLE2 variants. In a response, Mahajan and Bassuk (2016) maintained that the PRICKLE2 variants identified by Tao et al. (2011) contributed to the phenotype in their patients. (less)
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Pathogenic
(-)
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no assertion criteria provided
Method: clinical testing
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not provided
Affected status: yes
Allele origin:
germline
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Genome Diagnostics Laboratory, Amsterdam University Medical Center
Study: VKGL Data-share Consensus
Accession: SCV001807996.1 First in ClinVar: Aug 25, 2021 Last updated: Aug 25, 2021 |
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Pathogenic
(-)
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no assertion criteria provided
Method: clinical testing
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not provided
Affected status: yes
Allele origin:
germline
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Joint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+
Additional submitter:
Diagnostic Laboratory, Department of Genetics, University Medical Center Groningen
Study: VKGL Data-share Consensus
Accession: SCV001955733.1 First in ClinVar: Oct 02, 2021 Last updated: Oct 02, 2021 |
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Pathogenic
(-)
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no assertion criteria provided
Method: clinical testing
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not provided
Affected status: yes
Allele origin:
germline
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Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center
Additional submitter:
Diagnostic Laboratory, Department of Genetics, University Medical Center Groningen
Study: VKGL Data-share Consensus
Accession: SCV001968652.1 First in ClinVar: Oct 08, 2021 Last updated: Oct 08, 2021 |
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Pathogenic
(Sep 03, 2022)
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no assertion criteria provided
Method: clinical testing
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not provided
Affected status: yes
Allele origin:
germline
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Genetic Services Laboratory, University of Chicago
Accession: SCV003839906.1
First in ClinVar: Mar 18, 2023 Last updated: Mar 18, 2023 |
Comment:
DNA sequence analysis of the POLG gene demonstrated a sequence change, c.1399G>A, in exon 7 that results in an amino acid change, p.Ala467Thr. The p.Ala467Thr … (more)
DNA sequence analysis of the POLG gene demonstrated a sequence change, c.1399G>A, in exon 7 that results in an amino acid change, p.Ala467Thr. The p.Ala467Thr change affects a highly conserved amino acid residue located in a domain of the POLG protein that is known to be functional. In-silico pathogenicity prediction tools (SIFT, PolyPhen2, Align GVGD, REVEL) provide contradictory results for the p.Ala467Thr substitution. This pathogenic sequence change has previously been described as the most common POLG variant associated with autosomal recessive Alpers-Huttenlocher syndrome (PMID: 20301791). This sequence change has been associated with reduced enzyme activity (PMID: 20301791). This sequence change has been described in the gnomAD database with a frequency of 0.05% in the overall population (dbSNP rs113994095). These collective evidences indicate that this sequence change is pathogenic. (less)
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Pathogenic
(May 09, 2024)
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no assertion criteria provided
Method: clinical testing
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POLG-related condition
Affected status: unknown
Allele origin:
germline
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PreventionGenetics, part of Exact Sciences
Accession: SCV004116148.3
First in ClinVar: Nov 20, 2023 Last updated: Oct 08, 2024 |
Comment:
The POLG c.1399G>A variant is predicted to result in the amino acid substitution p.Ala467Thr. This variant has commonly been reported to be causative for autosomal … (more)
The POLG c.1399G>A variant is predicted to result in the amino acid substitution p.Ala467Thr. This variant has commonly been reported to be causative for autosomal recessive POLG-related disorders (Rajakulendran et al. 2016. PubMed ID: 26735972; Saneto et al. 2010. PubMed ID: 20138553; Van Goethem et al. 2001. PubMed ID: 11431686; Ferrari et al. 2005. PubMed ID: 15689359; Chan et al. 2005. PubMed ID: 16024923). In vitro functional studies have shown that this variant leads to loss of activity and binding affinity (Chan et al. 2005. PubMed ID: 16024923; Luoma et al. 2005. PubMed ID: 15917273; Kasahara et al. 2017. PubMed ID: 27987238). This variant is reported in 0.098% of alleles in individuals of European (Non-Finnish) descent in gnomAD. This variant is interpreted as pathogenic. (less)
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Pathogenic
(Apr 07, 2017)
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no assertion criteria provided
Method: clinical testing
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Mitochondrial disease
Affected status: yes
Allele origin:
germline
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Wellcome Centre for Mitochondrial Research, Newcastle University
Accession: SCV000575914.1
First in ClinVar: May 22, 2017 Last updated: May 22, 2017 |
Number of individuals with the variant: 1
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Pathogenic
(-)
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no assertion criteria provided
Method: clinical testing
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not provided
Affected status: yes
Allele origin:
germline
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Laboratory of Diagnostic Genome Analysis, Leiden University Medical Center (LUMC)
Study: VKGL Data-share Consensus
Accession: SCV001797643.1 First in ClinVar: Aug 21, 2021 Last updated: Aug 21, 2021 |
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Pathogenic
(-)
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no assertion criteria provided
Method: clinical testing
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not provided
Affected status: yes
Allele origin:
germline
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Diagnostic Laboratory, Department of Genetics, University Medical Center Groningen
Study: VKGL Data-share Consensus
Accession: SCV001743413.3 First in ClinVar: Jul 07, 2021 Last updated: Sep 08, 2021 |
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not provided
(-)
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no classification provided
Method: literature only
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Mitochondrial disease
Affected status: unknown
Allele origin:
germline
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GeneReviews
Accession: SCV000040905.3
First in ClinVar: Apr 04, 2013 Last updated: Oct 01, 2022 |
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not provided
(-)
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no classification provided
Method: phenotyping only
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POLG- Related Disorders
Affected status: yes
Allele origin:
unknown
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GenomeConnect, ClinGen
Accession: SCV000840346.1
First in ClinVar: Oct 14, 2018 Last updated: Oct 14, 2018 |
Comment:
GenomeConnect assertions are reported exactly as they appear on the patient-provided report from the testing laboratory. GenomeConnect staff make no attempt to reinterpret the clinical … (more)
GenomeConnect assertions are reported exactly as they appear on the patient-provided report from the testing laboratory. GenomeConnect staff make no attempt to reinterpret the clinical significance of the variant. (less)
Clinical Features:
Abnormal delivery (present) , Vertigo (present) , Conductive hearing impairment (present) , Seizures (present) , Depressivity (present) , Anxiety (present) , Abnormality of the stomach … (more)
Abnormal delivery (present) , Vertigo (present) , Conductive hearing impairment (present) , Seizures (present) , Depressivity (present) , Anxiety (present) , Abnormality of the stomach (present) , Feeding difficulties (present) (less)
Indication for testing: Diagnostic
Age: 10-19 years
Sex: male
Method: Sanger Sequencing
Testing laboratory: GeneDx
Date variant was reported to submitter: 2018-02-20
Testing laboratory interpretation: Pathogenic
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Germline Functional Evidence
There is no functional evidence in ClinVar for this variation. If you have generated functional data for this variation, please consider submitting that data to ClinVar. |
Citations for germline classification of this variant
HelpTitle | Author | Journal | Year | Link |
---|---|---|---|---|
POLG-Related Disorders. | Adam MP | - | 2024 | PMID: 20301791 |
NGS-Panel Diagnosis Developed for the Differential Diagnosis of Idiopathic Toe Walking and Its Application for the Investigation of Possible Genetic Causes for the Gait Anomaly. | Pomarino D | Global medical genetics | 2023 | PMID: 37091313 |
Accelerated genome sequencing with controlled costs for infants in intensive care units: a feasibility study in a French hospital network. | Denommé-Pichon AS | European journal of human genetics : EJHG | 2022 | PMID: 34782754 |
Integration of whole genome sequencing into a healthcare setting: high diagnostic rates across multiple clinical entities in 3219 rare disease patients. | Stranneheim H | Genome medicine | 2021 | PMID: 33726816 |
Ketogenic diet in a patient with refractory status epilepticus due to POLG mutation. | Koessler M | JIMD reports | 2020 | PMID: 33473333 |
Precision medicine integrating whole-genome sequencing, comprehensive metabolomics, and advanced imaging. | Hou YC | Proceedings of the National Academy of Sciences of the United States of America | 2020 | PMID: 31980526 |
Optimizing clinical exome design and parallel gene-testing for recessive genetic conditions in preconception carrier screening: Translational research genomic data from 14,125 exomes. | Capalbo A | PLoS genetics | 2019 | PMID: 31589614 |
The frequency of mitochondrial polymerase gamma related disorders in a large Polish population cohort. | Piekutowska-Abramczuk D | Mitochondrion | 2019 | PMID: 30423451 |
Whole Exome Sequencing Is the Preferred Strategy to Identify the Genetic Defect in Patients With a Probable or Possible Mitochondrial Cause. | Theunissen TEJ | Frontiers in genetics | 2018 | PMID: 30369941 |
Spectrum of movement disorders and neurotransmitter abnormalities in paediatric POLG disease. | Papandreou A | Journal of inherited metabolic disease | 2018 | PMID: 30167885 |
Diagnostic outcomes for genetic testing of 70 genes in 8565 patients with epilepsy and neurodevelopmental disorders. | Lindy AS | Epilepsia | 2018 | PMID: 29655203 |
The adjunctive application of transcranial direct current stimulation in the management of de novo refractory epilepsia partialis continua in adolescent-onset POLG-related mitochondrial disease. | Ng YS | Epilepsia open | 2018 | PMID: 29588995 |
Improved diagnostic yield compared with targeted gene sequencing panels suggests a role for whole-genome sequencing as a first-tier genetic test. | Lionel AC | Genetics in medicine : official journal of the American College of Medical Genetics | 2018 | PMID: 28771251 |
Decreased male reproductive success in association with mitochondrial dysfunction. | Martikainen MH | European journal of human genetics : EJHG | 2017 | PMID: 28812649 |
Enrichment of deleterious variants of mitochondrial DNA polymerase gene (POLG1) in bipolar disorder. | Kasahara T | Psychiatry and clinical neurosciences | 2017 | PMID: 27987238 |
Late-onset of Alpers-Huttenlocher syndrome: an unusual cause of refractory epilepsy and liver failure. | London F | Acta neurologica Belgica | 2017 | PMID: 27422324 |
Response to Sandford et al.: PRICKLE2 Variants in Epilepsy: A Call for Precision Medicine. | Mahajan VB | American journal of human genetics | 2016 | PMID: 26942292 |
PRICKLE2 Mutations Might Not Be Involved in Epilepsy. | Sandford E | American journal of human genetics | 2016 | PMID: 26942291 |
A Clinical, Neuropathological and Genetic Study of Homozygous A467T POLG-Related Mitochondrial Disease. | Rajakulendran S | PloS one | 2016 | PMID: 26735972 |
The spectrum of epilepsy caused by POLG mutations. | Janssen W | Acta neurologica Belgica | 2016 | PMID: 26104464 |
Cranial nerve and cervical root enhancement in an infant with polymerase gamma mutation mitochondrial disease. | Horst DM | Pediatric neurology | 2014 | PMID: 25286830 |
Valproic acid triggers increased mitochondrial biogenesis in POLG-deficient fibroblasts. | Sitarz KS | Molecular genetics and metabolism | 2014 | PMID: 24725338 |
Abnormalities in glycogen metabolism in a patient with alpers' syndrome presenting with hypoglycemia. | Simon M | JIMD reports | 2014 | PMID: 24272679 |
Reduced mitochondrial DNA content and heterozygous nuclear gene mutations in patients with acute liver failure. | Helbling D | Journal of pediatric gastroenterology and nutrition | 2013 | PMID: 23783014 |
Prospective study of POLG mutations presenting in children with intractable epilepsy: prevalence and clinical features. | Uusimaa J | Epilepsia | 2013 | PMID: 23448099 |
POLG mutation presenting with late-onset jerky torticollis. | Tuladhar AM | Journal of neurology | 2013 | PMID: 23212759 |
An informatics approach to analyzing the incidentalome. | Berg JS | Genetics in medicine : official journal of the American College of Medical Genetics | 2013 | PMID: 22995991 |
What is influencing the phenotype of the common homozygous polymerase-γ mutation p.Ala467Thr? | Neeve VC | Brain : a journal of neurology | 2012 | PMID: 23250882 |
Early-onset ataxia with progressive external ophthalmoplegia associated with POLG mutation: autosomal recessive mitochondrial ataxic syndrome or SANDO? | Habek M | The neurologist | 2012 | PMID: 22931735 |
Screening for POLG W748S and A467T mutations in ataxia patients from Spain. | Pelayo-Negro AL | Movement disorders : official journal of the Movement Disorder Society | 2012 | PMID: 22711370 |
Polymerase gamma deficiency (POLG): clinical course in a child with a two stage evolution from infantile myocerebrohepatopathy spectrum to an Alpers syndrome and neuropathological findings of Leigh's encephalopathy. | Scalais E | European journal of paediatric neurology : EJPN : official journal of the European Paediatric Neurology Society | 2012 | PMID: 22342071 |
Sensory neuronopathy in patients harbouring recessive polymerase γ mutations. | Lax NZ | Brain : a journal of neurology | 2012 | PMID: 22189570 |
Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE)-like phenotype: an expanded clinical spectrum of POLG1 mutations. | Tang S | Journal of neurology | 2012 | PMID: 21993618 |
MELAS/SANDO overlap syndrome associated with POLG1 mutations. | Hansen N | Neurological sciences : official journal of the Italian Neurological Society and of the Italian Society of Clinical Neurophysiology | 2012 | PMID: 21647632 |
Stroke and Stroke-Like Symptoms in Patients with Mutations in the POLG1 Gene. | Brinjikji W | JIMD reports | 2011 | PMID: 23430834 |
Sensory ataxic neuropathy with dysarthria/dysphagia and ophthalmoplegia (SANDO). Two case reports. | Gáti I | Acta myologica : myopathies and cardiomyopathies : official journal of the Mediterranean Society of Myology | 2011 | PMID: 22616202 |
Bowel obstruction in patients with Alpers-Huttenlocher syndrome. | Spiegler J | Neuropediatrics | 2011 | PMID: 22006280 |
Mitochondrial DNA polymerase gamma mutations: an ever expanding molecular and clinical spectrum. | Tang S | Journal of medical genetics | 2011 | PMID: 21880868 |
Parieto-occipital lobe epilepsy caused by a POLG1 compound heterozygous A467T/W748S genotype. | Roshal D | Epilepsy & behavior : E&B | 2011 | PMID: 21515089 |
Mutations in prickle orthologs cause seizures in flies, mice, and humans. | Tao H | American journal of human genetics | 2011 | PMID: 21276947 |
Molecular and biochemical characterisation of a novel mutation in POLG associated with Alpers syndrome. | Schaller A | BMC neurology | 2011 | PMID: 21235791 |
POLG exon 22 skipping induced by different mechanisms in two unrelated cases of Alpers syndrome. | Mousson de Camaret B | Mitochondrion | 2011 | PMID: 20691285 |
Mitochondrial DNA depletion and fatal infantile hepatic failure due to mutations in the mitochondrial polymerase γ (POLG) gene: a combined morphological/enzyme histochemical and immunocytochemical/biochemical and molecular genetic study. | Müller-Höcker J | Journal of cellular and molecular medicine | 2011 | PMID: 19538466 |
POLG1 variations presenting as multiple sclerosis. | Echaniz-Laguna A | Archives of neurology | 2010 | PMID: 20837861 |
High-throughput, pooled sequencing identifies mutations in NUBPL and FOXRED1 in human complex I deficiency. | Calvo SE | Nature genetics | 2010 | PMID: 20818383 |
[Mitochondrial DNA depletion and POLG mutations in a patient with sensory ataxia, dysarthria and ophthalmoplegia]. | Posada IJ | Medicina clinica | 2010 | PMID: 20576279 |
A novel POLG gene mutation in 4 children with Alpers-like hepatocerebral syndromes. | Kurt B | Archives of neurology | 2010 | PMID: 20142534 |
POLG DNA testing as an emerging standard of care before instituting valproic acid therapy for pediatric seizure disorders. | Saneto RP | Seizure | 2010 | PMID: 20138553 |
Sensory ataxic neuropathy dysarthria and ophthalmoparesis (SANDO) in a sibling pair with a homozygous p.A467T POLG mutation. | McHugh JC | Muscle & nerve | 2010 | PMID: 19813183 |
Cerebral folate deficiency and CNS inflammatory markers in Alpers disease. | Hasselmann O | Molecular genetics and metabolism | 2010 | PMID: 19766516 |
Reversible valproate hepatotoxicity due to mutations in mitochondrial DNA polymerase γ (POLG1). | McFarland R | BMJ case reports | 2009 | PMID: 21686371 |
The unfolding clinical spectrum of POLG mutations. | Blok MJ | Journal of medical genetics | 2009 | PMID: 19578034 |
De novo mutation in POLG leads to haplotype insufficiency and Alpers syndrome. | Chan SS | Mitochondrion | 2009 | PMID: 19501198 |
Novel POLG1 mutations associated with neuromuscular and liver phenotypes in adults and children. | Stewart JD | Journal of medical genetics | 2009 | PMID: 19251978 |
DNA polymerase gamma and mitochondrial disease: understanding the consequence of POLG mutations. | Chan SS | Biochimica et biophysica acta | 2009 | PMID: 19010300 |
Proof of progression over time: finally fulminant brain, muscle, and liver affection in Alpers syndrome associated with the A467T POLG1 mutation. | Boes M | Seizure | 2009 | PMID: 18783964 |
Apraxia of lid opening mimicking ptosis in compound heterozygosity for A467T and W748S POLG1 mutations. | Paus S | Movement disorders : official journal of the Movement Disorder Society | 2008 | PMID: 18546343 |
Normal biochemical analysis of the oxidative phosphorylation (OXPHOS) system in a child with POLG mutations: a cautionary note. | de Vries MC | Journal of inherited metabolic disease | 2008 | PMID: 18500570 |
The A467T and W748S POLG substitutions are a rare cause of adult-onset ataxia in Europe. | Craig K | Brain : a journal of neurology | 2007 | PMID: 17438011 |
Abundance of the POLG disease mutations in Europe, Australia, New Zealand, and the United States explained by single ancient European founders. | Hakonen AH | European journal of human genetics : EJHG | 2007 | PMID: 17426723 |
POLG1 mutations associated with progressive encephalopathy in childhood. | Kollberg G | Journal of neuropathology and experimental neurology | 2006 | PMID: 16896309 |
The spectrum of clinical disease caused by the A467T and W748S POLG mutations: a study of 26 cases. | Tzoulis C | Brain : a journal of neurology | 2006 | PMID: 16638794 |
Mitochondrial and nuclear DNA defects in Saccharomyces cerevisiae with mutations in DNA polymerase gamma associated with progressive external ophthalmoplegia. | Stuart GR | Human molecular genetics | 2006 | PMID: 16368709 |
POLG mutations in Alpers syndrome. | Nguyen KV | Neurology | 2005 | PMID: 16177225 |
POLG mutations associated with Alpers syndrome and mitochondrial DNA depletion. | Naviaux RK | Annals of neurology | 2005 | PMID: 16130100 |
The common A467T mutation in the human mitochondrial DNA polymerase (POLG) compromises catalytic efficiency and interaction with the accessory subunit. | Chan SS | The Journal of biological chemistry | 2005 | PMID: 16024923 |
Functional defects due to spacer-region mutations of human mitochondrial DNA polymerase in a family with an ataxia-myopathy syndrome. | Luoma PT | Human molecular genetics | 2005 | PMID: 15917273 |
Autosomal recessive mitochondrial ataxic syndrome due to mitochondrial polymerase gamma mutations. | Winterthun S | Neurology | 2005 | PMID: 15824347 |
Infantile hepatocerebral syndromes associated with mutations in the mitochondrial DNA polymerase-gammaA. | Ferrari G | Brain : a journal of neurology | 2005 | PMID: 15689359 |
POLG mutations in neurodegenerative disorders with ataxia but no muscle involvement. | Van Goethem G | Neurology | 2004 | PMID: 15477547 |
POLG mutations associated with Alpers' syndrome and mitochondrial DNA depletion. | Naviaux RK | Annals of neurology | 2004 | PMID: 15122711 |
Patient homozygous for a recessive POLG mutation presents with features of MERRF. | Van Goethem G | Neurology | 2003 | PMID: 14694057 |
Recessive POLG mutations presenting with sensory and ataxic neuropathy in compound heterozygote patients with progressive external ophthalmoplegia. | Van Goethem G | Neuromuscular disorders : NMD | 2003 | PMID: 12565911 |
Adult-onset autosomal recessive ataxia with thalamic lesions in a Finnish family. | Rantamäki M | Neurology | 2001 | PMID: 11571332 |
Mutation of POLG is associated with progressive external ophthalmoplegia characterized by mtDNA deletions. | Van Goethem G | Nature genetics | 2001 | PMID: 11431686 |
Progressive myoclonus and epilepsy with dentatorubral degeneration: a clinicopathological study of the Ramsay Hunt syndrome. | Bird TD | Journal of neurology, neurosurgery, and psychiatry | 1978 | PMID: 632821 |
http://www.egl-eurofins.com/emvclass/emvclass.php?approved_symbol=POLG | - | - | - | - |
Van Broeckhoven, C. Personal Communication. 2004. Antwerp, Belgium | - | - | - | - |
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Text-mined citations for rs113994095 ...
HelpRecord last updated Nov 03, 2024
This date represents the last time this VCV record was updated. The update may be due to an update to one of the included submitted records (SCVs), or due to an update that ClinVar made to the variant such as adding HGVS expressions or a rs number. So this date may be different from the date of the “most recent submission” reported at the top of this page.