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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

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
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
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
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
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

Prevalence, Clinical Features, Neuroimaging, and Genetic Findings in Children With Ataxic Cerebral Palsy in Europe.
Horber V, Andersen GL, Arnaud C, De La Cruz J, Dakovic I, Greitane A, Hensey O, Himmelmann K, Hollody K, Horridge K, Künzle CT, Marcelli M, Ortibus E, Papavasiliou A, Perra O, Platt MJ, Rackauskaite G, Sigurdardottir S, Troha Gergeli A, Virella D, Krägeloh-Mann I, Sellier E
Neurology 2023 Dec 12;101(24):e2509-e2521. Epub 2023 Oct 19 doi: 10.1212/WNL.0000000000207851. PMID: 37857495Free PMC Article
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
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
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
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
Neurological findings and genetic alterations in patients with Kostmann syndrome and HAX1 mutations.
Roques G, Munzer M, Barthez MA, Beaufils S, Beaupain B, Flood T, Keren B, Bellanné-Chantelot C, Donadieu J
Pediatr Blood Cancer 2014 Jun;61(6):1041-8. Epub 2014 Jan 30 doi: 10.1002/pbc.24964. PMID: 24482108
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

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
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
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

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
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
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
Brain MR Imaging Findings in Woodhouse-Sakati Syndrome.
Abusrair AH, Bohlega S, Al-Semari A, Al-Ajlan FS, Al-Ahmadi K, Mohamed B, AlDakheel A
AJNR Am J Neuroradiol 2018 Dec;39(12):2256-2262. Epub 2018 Nov 8 doi: 10.3174/ajnr.A5879. PMID: 30409855Free PMC Article

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