U.S. flag

An official website of the United States government

Format

Send to:

Choose Destination

Intellectual disability, autosomal recessive 9(MRT9; MRT26)

MedGen UID:
369678
•Concept ID:
C1970195
•
Mental or Behavioral Dysfunction
Synonyms: MENTAL RETARDATION, AUTOSOMAL RECESSIVE 26; MRT9
 
Monarch Initiative: MONDO:0012617
OMIM®: 611095

Clinical features

From HPO
Growth delay
MedGen UID:
99124
•Concept ID:
C0456070
•
Pathologic Function
A deficiency or slowing down of growth pre- and postnatally.
See: Feature record | Search on this feature
Spasticity
MedGen UID:
7753
•Concept ID:
C0026838
•
Sign or Symptom
A motor disorder characterized by a velocity-dependent increase in tonic stretch reflexes with increased muscle tone, exaggerated (hyperexcitable) tendon reflexes.
See: Feature record | Search on this feature
Intellectual disability, severe
MedGen UID:
48638
•Concept ID:
C0036857
•
Mental or Behavioral Dysfunction
Severe mental retardation is defined as an intelligence quotient (IQ) in the range of 20-34.
See: Feature record | Search on this feature
Motor delay
MedGen UID:
381392
•Concept ID:
C1854301
•
Finding
A type of Developmental delay characterized by a delay in acquiring motor skills.
See: Feature record | Search on this feature
Intellectual disability
MedGen UID:
811461
•Concept ID:
C3714756
•
Mental or Behavioral Dysfunction
Intellectual disability, previously referred to as mental retardation, is characterized by subnormal intellectual functioning that occurs during the developmental period. It is defined by an IQ score below 70.
See: Feature record | Search on this feature
Show allHide all

Professional guidelines

PubMed

Genotype-phenotype correlation in contactin-associated protein-like 2 (CNTNAP-2) developmental disorder.
D'Onofrio G, Accogli A, Severino M, Caliskan H, Kokotović T, Blazekovic A, Jercic KG, Markovic S, Zigman T, Goran K, Barišić N, Duranovic V, Ban A, Borovecki F, Ramadža DP, Barić I, Fazeli W, Herkenrath P, Marini C, Vittorini R, Gowda V, Bouman A, Rocca C, Alkhawaja IA, Murtaza BN, Rehman MMU, Al Alam C, Nader G, Mancardi MM, Giacomini T, Srivastava S, Alvi JR, Tomoum H, Matricardi S, Iacomino M, Riva A, Scala M, Madia F, Pistorio A, Salpietro V, Minetti C, Rivière JB, Srour M, Efthymiou S, Maroofian R, Houlden H, Vernes SC, Zara F, Striano P, Nagy V
Hum Genet 2023 Jul;142(7):909-925. Epub 2023 May 14 doi: 10.1007/s00439-023-02552-2. PMID: 37183190Free PMC Article
Genotype-phenotype correlations in RHOBTB2-associated neurodevelopmental disorders.
Langhammer F, Maroofian R, Badar R, Gregor A, Rochman M, Ratliff JB, Koopmans M, Herget T, Hempel M, Kortüm F, Heron D, Mignot C, Keren B, Brooks S, Botti C, Ben-Zeev B, Argilli E, Sherr EH, Gowda VK, Srinivasan VM, Bakhtiari S, Kruer MC, Salih MA, Kuechler A, Muller EA, Blocker K, Kuismin O, Park KL, Kochhar A, Brown K, Ramanathan S, Clark RD, Elgizouli M, Melikishvili G, Tabatadze N, Stark Z, Mirzaa GM, Ong J, Grasshoff U, Bevot A, von Wintzingerode L, Jamra RA, Hennig Y, Goldenberg P, Al Alam C, Charif M, Boulouiz R, Bellaoui M, Amrani R, Al Mutairi F, Tamim AM, Abdulwahab F, Alkuraya FS, Khouj EM, Alvi JR, Sultan T, Hashemi N, Karimiani EG, Ashrafzadeh F, Imannezhad S, Efthymiou S, Houlden H, Sticht H, Zweier C
Genet Med 2023 Aug;25(8):100885. Epub 2023 May 8 doi: 10.1016/j.gim.2023.100885. PMID: 37165955
Genotype-phenotype correlation in Phelan-McDermid syndrome: A comprehensive review of chromosome 22q13 deleted genes.
Ricciardello A, Tomaiuolo P, Persico AM
Am J Med Genet A 2021 Jul;185(7):2211-2233. Epub 2021 May 5 doi: 10.1002/ajmg.a.62222. PMID: 33949759Free PMC Article

Recent clinical studies

Etiology

Can velmanase alfa be the next widespread potential therapy for alpha-mannosidosis?
Abdul Ghani S, Burney S, Ul Hussain H, Abdul Wahid M, Mumtaz H
Int J Surg 2023 Sep 1;109(9):2882-2885. doi: 10.1097/JS9.0000000000000528. PMID: 37352513Free PMC Article
Global developmental delay and intellectual disability in the era of genomics: Diagnosis and challenges in resource limited areas.
Masri AT, Oweis L, Ali M, Hamamy H
Clin Neurol Neurosurg 2023 Jul;230:107799. Epub 2023 May 22 doi: 10.1016/j.clineuro.2023.107799. PMID: 37236004
Bi-allelic TTI1 variants cause an autosomal-recessive neurodevelopmental disorder with microcephaly.
Serey-Gaut M, Cortes M, Makrythanasis P, Suri M, Taylor AMR, Sullivan JA, Asleh AN, Mitra J, Dar MA, McNamara A, Shashi V, Dugan S, Song X, Rosenfeld JA, Cabrol C, Iwaszkiewicz J, Zoete V, Pehlivan D, Akdemir ZC, Roeder ER, Littlejohn RO, Dibra HK, Byrd PJ, Stewart GS, Geckinli BB, Posey J, Westman R, Jungbluth C, Eason J, Sachdev R, Evans CA, Lemire G, VanNoy GE, O'Donnell-Luria A, Mau-Them FT, Juven A, Piard J, Nixon CY, Zhu Y, Ha T, Buckley MF, Thauvin C, Essien Umanah GK, Van Maldergem L, Lupski JR, Roscioli T, Dawson VL, Dawson TM, Antonarakis SE
Am J Hum Genet 2023 Mar 2;110(3):499-515. Epub 2023 Jan 31 doi: 10.1016/j.ajhg.2023.01.006. PMID: 36724785Free PMC Article
Documenting manifestations and impacts of autosomal recessive spastic ataxia of Charlevoix-Saguenay to develop patient-reported outcome.
Tremblay M, Girard-Côté L, Brais B, Gagnon C
Orphanet J Rare Dis 2022 Oct 1;17(1):369. doi: 10.1186/s13023-022-02497-1. PMID: 36183078Free PMC Article
Acro-cardio-facial syndrome.
Digilio MC, Dallapiccola B
Orphanet J Rare Dis 2010 Sep 29;5:25. doi: 10.1186/1750-1172-5-25. PMID: 20920258Free PMC Article

Diagnosis

Landscape of genetic infantile epileptic spasms syndrome-A multicenter cohort of 124 children from India.
Nagarajan B, Gowda VK, Yoganathan S, Sharawat IK, Srivastava K, Vora N, Badheka R, Danda S, Kalane U, Kaur A, Madaan P, Mehta S, Negi S, Panda PK, Rajadhyaksha S, Saini AG, Saini L, Shah S, Srinivasan VM, Suthar R, Thomas M, Vyas S, Sankhyan N, Sahu JK
Epilepsia Open 2023 Dec;8(4):1383-1404. Epub 2023 Aug 25 doi: 10.1002/epi4.12811. PMID: 37583270Free PMC Article
Can velmanase alfa be the next widespread potential therapy for alpha-mannosidosis?
Abdul Ghani S, Burney S, Ul Hussain H, Abdul Wahid M, Mumtaz H
Int J Surg 2023 Sep 1;109(9):2882-2885. doi: 10.1097/JS9.0000000000000528. PMID: 37352513Free PMC Article
Global developmental delay and intellectual disability in the era of genomics: Diagnosis and challenges in resource limited areas.
Masri AT, Oweis L, Ali M, Hamamy H
Clin Neurol Neurosurg 2023 Jul;230:107799. Epub 2023 May 22 doi: 10.1016/j.clineuro.2023.107799. PMID: 37236004
Diagnostic Yield and Novel Candidate Genes by Exome Sequencing in 152 Consanguineous Families With Neurodevelopmental Disorders.
Reuter MS, Tawamie H, Buchert R, Hosny Gebril O, Froukh T, Thiel C, Uebe S, Ekici AB, Krumbiegel M, Zweier C, Hoyer J, Eberlein K, Bauer J, Scheller U, Strom TM, Hoffjan S, Abdelraouf ER, Meguid NA, Abboud A, Al Khateeb MA, Fakher M, Hamdan S, Ismael A, Muhammad S, Abdallah E, Sticht H, Wieczorek D, Reis A, Abou Jamra R
JAMA Psychiatry 2017 Mar 1;74(3):293-299. doi: 10.1001/jamapsychiatry.2016.3798. PMID: 28097321
Acro-cardio-facial syndrome.
Digilio MC, Dallapiccola B
Orphanet J Rare Dis 2010 Sep 29;5:25. doi: 10.1186/1750-1172-5-25. PMID: 20920258Free PMC Article

Therapy

Can velmanase alfa be the next widespread potential therapy for alpha-mannosidosis?
Abdul Ghani S, Burney S, Ul Hussain H, Abdul Wahid M, Mumtaz H
Int J Surg 2023 Sep 1;109(9):2882-2885. doi: 10.1097/JS9.0000000000000528. PMID: 37352513Free PMC Article
Patients with Lately Diagnosed Cerebrotendinous Xanthomatosis.
Yunisova G, Tufekcioglu Z, Dogu O, Bilgic B, Kaleagasi H, Akca Kalem S, Lohmann E, Gurvit HI, Emre M, Hanagasi HA
Neurodegener Dis 2019;19(5-6):218-224. Epub 2020 Apr 29 doi: 10.1159/000506770. PMID: 32349000
Mabry Syndrome in a Child of South Asian Descent.
Sohail AH, Durrani MYK, Ibrahim SH, Humayun KN
J Coll Physicians Surg Pak 2018 Sep;28(9):S192-S194. doi: 10.29271/jcpsp.2018.09.S192. PMID: 30173695
Clinical whole exome sequencing in child neurology practice.
Srivastava S, Cohen JS, Vernon H, Barañano K, McClellan R, Jamal L, Naidu S, Fatemi A
Ann Neurol 2014 Oct;76(4):473-83. Epub 2014 Aug 30 doi: 10.1002/ana.24251. PMID: 25131622
The neurology of carbonic anhydrase type II deficiency syndrome.
Bosley TM, Salih MA, Alorainy IA, Islam MZ, Oystreck DT, Suliman OS, al Malki S, Suhaibani AH, Khiari H, Beckers S, van Wesenbeeck L, Perdu B, AlDrees A, Elmalik SA, Van Hul W, Abu-Amero KK
Brain 2011 Dec;134(Pt 12):3502-15. Epub 2011 Nov 26 doi: 10.1093/brain/awr302. PMID: 22120147

Prognosis

Biallelic variants in NSUN6 cause an autosomal recessive neurodevelopmental disorder.
Mattioli F, Worpenberg L, Li CT, Ibrahim N, Naz S, Sharif S, Firouzabadi SG, Vosoogh S, Saraeva-Lamri R, Raymond L, Trujillo C, Guex N, Antonarakis SE, Ansar M, Darvish H, Liu RJ, Roignant JY, Reymond A
Genet Med 2023 Sep;25(9):100900. Epub 2023 May 21 doi: 10.1016/j.gim.2023.100900. PMID: 37226891
The clinical and genetic spectrum of autosomal-recessive TOR1A-related disorders.
Saffari A, Lau T, Tajsharghi H, Karimiani EG, Kariminejad A, Efthymiou S, Zifarelli G, Sultan T, Toosi MB, Sedighzadeh S, Siu VM, Ortigoza-Escobar JD, AlShamsi AM, Ibrahim S, Al-Sannaa NA, Al-Hertani W, Sandra W, Tarnopolsky M, Alavi S, Li C, Day-Salvatore DL, Martínez-González MJ, Levandoski KM, Bedoukian E, Madan-Khetarpal S, Idleburg MJ, Menezes MJ, Siddharth A, Platzer K, Oppermann H, Smitka M, Collins F, Lek M, Shahrooei M, Ghavideldarestani M, Herman I, Rendu J, Faure J, Baker J, Bhambhani V, Calderwood L, Akhondian J, Imannezhad S, Mirzadeh HS, Hashemi N, Doosti M, Safi M, Ahangari N, Torbati PN, Abedini S, Salpietro V, Gulec EY, Eshaghian S, Ghazavi M, Pascher MT, Vogel M, Abicht A, Moutton S, Bruel AL, Rieubland C, Gallati S, Strom TM, Lochmüller H, Mohammadi MH, Alvi JR, Zackai EH, Keena BA, Skraban CM, Berger SI, Andrew EH, Rahimian E, Morrow MM, Wentzensen IM, Millan F, Henderson LB, Dafsari HS, Jungbluth H, Gomez-Ospina N, McRae A, Peter M, Veltra D, Marinakis NM, Sofocleous C, Ashrafzadeh F, Pehlivan D, Lemke JR, Melki J, Benezit A, Bauer P, Weis D, Lupski JR, Senderek J, Christodoulou J, Chung WK, Goodchild R, Offiah AC, Moreno-De-Luca A, Suri M, Ebrahimi-Fakhari D, Houlden H, Maroofian R
Brain 2023 Aug 1;146(8):3273-3288. doi: 10.1093/brain/awad039. PMID: 36757831Free PMC Article
TMEM63C mutations cause mitochondrial morphology defects and underlie hereditary spastic paraplegia.
Tábara LC, Al-Salmi F, Maroofian R, Al-Futaisi AM, Al-Murshedi F, Kennedy J, Day JO, Courtin T, Al-Khayat A, Galedari H, Mazaheri N, Protasoni M, Johnson M, Leslie JS, Salter CG, Rawlins LE, Fasham J, Al-Maawali A, Voutsina N, Charles P, Harrold L, Keren B, Kunji ERS, Vona B, Jelodar G, Sedaghat A, Shariati G, Houlden H, Crosby AH, Prudent J, Baple EL
Brain 2022 Sep 14;145(9):3095-3107. doi: 10.1093/brain/awac123. PMID: 35718349Free PMC Article
Psychiatric manifestations in cerebrotendinous xanthomatosis.
Fraidakis MJ
Transl Psychiatry 2013 Sep 3;3(9):e302. doi: 10.1038/tp.2013.76. PMID: 24002088Free PMC Article
Acro-cardio-facial syndrome.
Digilio MC, Dallapiccola B
Orphanet J Rare Dis 2010 Sep 29;5:25. doi: 10.1186/1750-1172-5-25. PMID: 20920258Free PMC Article

Clinical prediction guides

Landscape of genetic infantile epileptic spasms syndrome-A multicenter cohort of 124 children from India.
Nagarajan B, Gowda VK, Yoganathan S, Sharawat IK, Srivastava K, Vora N, Badheka R, Danda S, Kalane U, Kaur A, Madaan P, Mehta S, Negi S, Panda PK, Rajadhyaksha S, Saini AG, Saini L, Shah S, Srinivasan VM, Suthar R, Thomas M, Vyas S, Sankhyan N, Sahu JK
Epilepsia Open 2023 Dec;8(4):1383-1404. Epub 2023 Aug 25 doi: 10.1002/epi4.12811. PMID: 37583270Free PMC Article
Biallelic variants in NSUN6 cause an autosomal recessive neurodevelopmental disorder.
Mattioli F, Worpenberg L, Li CT, Ibrahim N, Naz S, Sharif S, Firouzabadi SG, Vosoogh S, Saraeva-Lamri R, Raymond L, Trujillo C, Guex N, Antonarakis SE, Ansar M, Darvish H, Liu RJ, Roignant JY, Reymond A
Genet Med 2023 Sep;25(9):100900. Epub 2023 May 21 doi: 10.1016/j.gim.2023.100900. PMID: 37226891
Genotype-phenotype correlations in RHOBTB2-associated neurodevelopmental disorders.
Langhammer F, Maroofian R, Badar R, Gregor A, Rochman M, Ratliff JB, Koopmans M, Herget T, Hempel M, Kortüm F, Heron D, Mignot C, Keren B, Brooks S, Botti C, Ben-Zeev B, Argilli E, Sherr EH, Gowda VK, Srinivasan VM, Bakhtiari S, Kruer MC, Salih MA, Kuechler A, Muller EA, Blocker K, Kuismin O, Park KL, Kochhar A, Brown K, Ramanathan S, Clark RD, Elgizouli M, Melikishvili G, Tabatadze N, Stark Z, Mirzaa GM, Ong J, Grasshoff U, Bevot A, von Wintzingerode L, Jamra RA, Hennig Y, Goldenberg P, Al Alam C, Charif M, Boulouiz R, Bellaoui M, Amrani R, Al Mutairi F, Tamim AM, Abdulwahab F, Alkuraya FS, Khouj EM, Alvi JR, Sultan T, Hashemi N, Karimiani EG, Ashrafzadeh F, Imannezhad S, Efthymiou S, Houlden H, Sticht H, Zweier C
Genet Med 2023 Aug;25(8):100885. Epub 2023 May 8 doi: 10.1016/j.gim.2023.100885. PMID: 37165955
The clinical and genetic spectrum of autosomal-recessive TOR1A-related disorders.
Saffari A, Lau T, Tajsharghi H, Karimiani EG, Kariminejad A, Efthymiou S, Zifarelli G, Sultan T, Toosi MB, Sedighzadeh S, Siu VM, Ortigoza-Escobar JD, AlShamsi AM, Ibrahim S, Al-Sannaa NA, Al-Hertani W, Sandra W, Tarnopolsky M, Alavi S, Li C, Day-Salvatore DL, Martínez-González MJ, Levandoski KM, Bedoukian E, Madan-Khetarpal S, Idleburg MJ, Menezes MJ, Siddharth A, Platzer K, Oppermann H, Smitka M, Collins F, Lek M, Shahrooei M, Ghavideldarestani M, Herman I, Rendu J, Faure J, Baker J, Bhambhani V, Calderwood L, Akhondian J, Imannezhad S, Mirzadeh HS, Hashemi N, Doosti M, Safi M, Ahangari N, Torbati PN, Abedini S, Salpietro V, Gulec EY, Eshaghian S, Ghazavi M, Pascher MT, Vogel M, Abicht A, Moutton S, Bruel AL, Rieubland C, Gallati S, Strom TM, Lochmüller H, Mohammadi MH, Alvi JR, Zackai EH, Keena BA, Skraban CM, Berger SI, Andrew EH, Rahimian E, Morrow MM, Wentzensen IM, Millan F, Henderson LB, Dafsari HS, Jungbluth H, Gomez-Ospina N, McRae A, Peter M, Veltra D, Marinakis NM, Sofocleous C, Ashrafzadeh F, Pehlivan D, Lemke JR, Melki J, Benezit A, Bauer P, Weis D, Lupski JR, Senderek J, Christodoulou J, Chung WK, Goodchild R, Offiah AC, Moreno-De-Luca A, Suri M, Ebrahimi-Fakhari D, Houlden H, Maroofian R
Brain 2023 Aug 1;146(8):3273-3288. doi: 10.1093/brain/awad039. PMID: 36757831Free PMC Article
TTC5 syndrome: Clinical and molecular spectrum of a severe and recognizable condition.
Musante L, Faletra F, Meier K, Tomoum H, Najarzadeh Torbati P, Blair E, North S, Gärtner J, Diegmann S, Beiraghi Toosi M, Ashrafzadeh F, Ghayoor Karimiani E, Murphy D, Murru FM, Zanus C, Magnolato A, La Bianca M, Feresin A, Girotto G, Gasparini P, Costa P, Carrozzi M
Am J Med Genet A 2022 Sep;188(9):2652-2665. Epub 2022 Jun 7 doi: 10.1002/ajmg.a.62852. PMID: 35670379Free PMC Article

Supplemental Content

Table of contents

    Clinical resources

    Practice guidelines

    • PubMed
      See practice and clinical guidelines in PubMed. The search results may include broader topics and may not capture all published guidelines. See the FAQ for details.

    Reviews

    Related information

    • Gene
      Related information in NCBI Gene
    • MeSH
      Related Medical Subject Headings
    • OMIM
      Related records in OMIM
    • PMC Articles
      Related information in PubMed Central Links
    • PubMed
      Related literature resources in PubMed

    Recent activity

    Clear Turn Off Turn On

    Your browsing activity is empty.

    Activity recording is turned off.

    Turn recording back on

    See more...