Galactosemia Mutation Panel
GTR Test Accession: Help GTR000607893.1
Last updated in GTR: 2023-06-06
Last annual review date for the lab: 2024-05-28 LinkOut
At a Glance
Diagnosis; Screening
Galactosemia; Disorder of galactose metabolism
Genes (1): Help
GALT (9p13.3)
Molecular Genetics - Targeted variant analysis: PCR with allele specific hybridization
This genetic variant panel is recommended for individuals with a …
Not provided
Not provided
Ordering Information
Offered by: Help
Test short name: Help
Specimen Source: Help
Who can order: Help
  • Genetic Counselor
  • Health Care Provider
  • Licensed Dentist
  • Licensed Physician
  • Nurse Practitioner
  • Physician Assistant
  • Public Health Mandate
  • Registered Nurse
Lab contact: Help
Elizabeth Selner, MS, CGC, Certified Genetic counselor, CGC, Genetic Counselor
Contact Policy: Help
Laboratory can only accept contact from health care providers. Patients/families are encouraged to discuss genetic testing options with their health care provider.
How to Order: Help
Order URL
Informed consent required: Help
Based on applicable state law
Pre-test genetic counseling required: Help
Decline to answer
Post-test genetic counseling required: Help
Decline to answer
Recommended fields not provided:
Conditions Help
Total conditions: 2
Condition/Phenotype Identifier
Test Targets
Genes Help
Total genes: 1
Gene Associated Condition Germline or Somatic Allele (Lab-provided) Variant in NCBI
Total methods: 1
Method Category Help
Test method Help
Targeted variant analysis
PCR with allele specific hybridization
ThermoFisher GeneTitan platform
Clinical Information
Test purpose: Help
Diagnosis; Screening
Target population: Help
This genetic variant panel is recommended for individuals with a GALT enzyme value less than 24.5 nmol/h/mg of hemoglobin.
View citations (4)
  • Molecular basis of disorders of human galactose metabolism: past, present, and future. Novelli G, et al. Mol Genet Metab. 2000;71(1-2):62-5. doi:10.1006/mgme.2000.3073. PMID: 11001796.
  • The molecular biology of galactosemia. Elsas LJ, et al. Genet Med. 1998;1(1):40-8. doi:10.1097/00125817-199811000-00009. PMID: 11261429.
  • Newborn screening fact sheets. Kaye CI, et al. Pediatrics. 2006;118(3):e934-63. doi:10.1542/peds.2006-1783. PMID: 16950973.
  • Welling L, Bernstein LE, Berry GT, Burlina AB, Eyskens F, Gautschi M, Grünewald S, Gubbels CS, Knerr I, Labrune P, van der Lee JH, MacDonald A, Murphy E, Portnoi PA, Õunap K, Potter NL, Rubio-Gozalbo ME, Spencer JB, Timmers I, Treacy EP, Van Calcar SC, Waisbren SE, Bosch AM, . International clinical guideline for the management of classical galactosemia: diagnosis, treatment, and follow-up. J Inherit Metab Dis. 2017;40(2):171-176. doi:10.1007/s10545-016-9990-5. Epub 2016 Nov 17. PMID: 27858262.
Variant Interpretation:
What is the protocol for interpreting a variation as a VUS? Help
All detected variants are evaluated according to the most recent American College of Medical Genetics and Genomics (ACMG) and Association for Molecular Pathology (AMP) recommendations. Variants are classified based on known, predicted, or possible pathogenicity and reported with interpretive comments detailing their potential or known significance.

Are family members with defined clinical status recruited to assess significance of VUS without charge? Help

Will the lab re-contact the ordering physician if variant interpretation changes? Help
No. The laboratory encourages health care providers to contact the laboratory at any time to learn how the status of a particular variant may have changed over time.
Is research allowed on the sample after clinical testing is complete? Help
Research testing is only performed under IRB approved protocol with an opt-out policy in place.
Recommended fields not provided:
Technical Information
Test Procedure: Help
The targeted genotyping assay utilizing the ThermoFisher GeneTitan platform is used to detect 24 targets in the GALT gene. Confirmatory testing of homozygous results is performed as reflex tests when appropriate. For details regarding the targeted pathogenic variants identified by this test, see the Targeted Variants table in Clinical Information. … View more
Test Confirmation: Help
Multiplex ligation-dependent probe amplification, polymerase chain reaction (PCR), relative quantitative PCR, and Sanger sequencing are used to confirm variants detected by array when appropriate.(Unpublished Mayo method)
Availability: Help
Tests performed
Entire test performed in-house
Analytical Validity: Help
Analytical sensitivity, specificity, and accuracy are ≥ 99%.
Assay limitations: Help
This assay will not detect all of the known disease-associated variants that cause galactosemia. Therefore, the absence of a detectable variant does not rule out the possibility that an individual is a carrier of or affected with this disease. Many disorders may present with symptoms similar to those associated with … View more
Proficiency testing (PT):
Is proficiency testing performed for this test? Help

Method used for proficiency testing: Help
Formal PT program

PT Provider: Help
American College of Medical Genetics / College of American Pathologists, ACMG/CAP
Software used to interpret novel variations Help
Variants may be analyzed using any combination of the following: Alamut, REVEL, Polyphen-2, SIFT, AGVGD, MutationTaster, SpliceSiteFinder-like, MaxEntScan, NNSPLICE, GeneSplicer, gene-specific online databases, ISCA, UCSC Genome Browser

Laboratory's policy on reporting novel variations Help
All novel alterations and copy number variants are evaluated for potential pathogenicity and included in the written report, accordingly.
Recommended fields not provided:
Regulatory Approval
FDA Review: Help
Category: FDA exercises enforcement discretion
Additional Information

IMPORTANT NOTE: NIH does not independently verify information submitted to GTR; it relies on submitters to provide information that is accurate and not misleading. NIH makes no endorsements of tests or laboratories listed in GTR. GTR is not a substitute for medical advice. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.