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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
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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

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
Auditory phenotype of Smith-Lemli-Opitz syndrome.
Zalewski CK, Sydlowski SA, King KA, Bianconi S, Dang Do A, Porter FD, Brewer CC
Am J Med Genet A 2021 Apr;185(4):1131-1141. Epub 2021 Feb 2 doi: 10.1002/ajmg.a.62087. PMID: 33529473Free PMC Article
Smith-Lemli-Opitz syndrome: clinical and biochemical correlates.
Donoghue SE, Pitt JJ, Boneh A, White SM
J Pediatr Endocrinol Metab 2018 Mar 28;31(4):451-459. doi: 10.1515/jpem-2017-0501. PMID: 29455191
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

Diagnosis

Spectrum of neuro-genetic disorders in the United Arab Emirates national population.
Saleh S, Beyyumi E, Al Kaabi A, Hertecant J, Barakat D, Al Dhaheri NS, Al-Gazali L, Al Shamsi A
Clin Genet 2021 Nov;100(5):573-600. Epub 2021 Aug 19 doi: 10.1111/cge.14044. PMID: 34374989
Auditory phenotype of Smith-Lemli-Opitz syndrome.
Zalewski CK, Sydlowski SA, King KA, Bianconi S, Dang Do A, Porter FD, Brewer CC
Am J Med Genet A 2021 Apr;185(4):1131-1141. Epub 2021 Feb 2 doi: 10.1002/ajmg.a.62087. PMID: 33529473Free PMC Article
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
Pseudoaminopterin syndrome.
Kraoua L, Capri Y, Perrin L, Benmansour A, Verloes A
Am J Med Genet A 2012 Sep;158A(9):2233-8. Epub 2012 Jul 18 doi: 10.1002/ajmg.a.35212. PMID: 22811276
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

A novel large intragenic DPYD deletion causing dihydropyrimidine dehydrogenase deficiency: a case report.
Malekkou A, Tomazou M, Mavrikiou G, Dionysiou M, Georgiou T, Papaevripidou I, Alexandrou A, Sismani C, Drousiotou A, Grafakou O, Petrou PP
BMC Med Genomics 2024 Mar 25;17(1):78. doi: 10.1186/s12920-024-01846-2. PMID: 38528593Free 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
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
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
Smith-Lemli-Opitz syndrome: clinical and biochemical correlates.
Donoghue SE, Pitt JJ, Boneh A, White SM
J Pediatr Endocrinol Metab 2018 Mar 28;31(4):451-459. doi: 10.1515/jpem-2017-0501. PMID: 29455191
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

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
Auditory phenotype of Smith-Lemli-Opitz syndrome.
Zalewski CK, Sydlowski SA, King KA, Bianconi S, Dang Do A, Porter FD, Brewer CC
Am J Med Genet A 2021 Apr;185(4):1131-1141. Epub 2021 Feb 2 doi: 10.1002/ajmg.a.62087. PMID: 33529473Free PMC Article

Recent systematic reviews

Autosomal Recessive Guanosine Triphosphate Cyclohydrolase I Deficiency: Redefining the Phenotypic Spectrum and Outcomes.
Novelli M, Tolve M, Quiroz V, Carducci C, Bove R, Ricciardi G, Yang K, Manti F, Pisani F, Ebrahimi-Fakhari D, Galosi S, Leuzzi V
Mov Disord Clin Pract 2024 Sep;11(9):1072-1084. Epub 2024 Jul 12 doi: 10.1002/mdc3.14157. PMID: 39001623Free PMC Article

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