Partington X-Linked Mental Retardation Syndrome (ARX)
| Dred_ID | RD00021 |
| OMIM ID | 309510 |
| Disease name | Partington X-Linked Mental Retardation Syndrome |
| Alternative names | Prts Mental Retardation, X-linked, Syndromic 1 Mrxs1 Mental Retardation, X-linked, with Dystonic Movements, Ataxia, and Seizures Mental Retardation, X-linked 36 Mrx36 |
| Category | Genetic diseases, Rare diseases, Neuronal diseases, Mental diseases |
| Phenotype | NIH Rare Diseases: Partington syndrome is a rare neurological condition that is primarily characterized by mild to moderate intellectual disability and dystonia of the hands. Other signs and symptoms may include dysarthria, behavioral abnormalities, recurrent seizures and/or an unusual gait (style of walking). Partington syndrome usually occurs in males; when it occurs in females, the signs and symptoms are often less severe. It is caused by changes (mutations) in the ARX gene and is inherited in an X-linked recessive manner. Treatment is based on the signs and symptoms present in each person.
OMIM: Partington syndrome is an X-linked developmental disorder characterized by mental retardation and variable movement disturbances. Partington syndrome is part of a phenotypic spectrum of disorders caused by mutation in the ARX gene comprising a nearly continuous series of developmental disorders ranging from hydranencephaly and lissencephaly (LISX2; 300215) to Proud syndrome (300004) to infantile spasms without brain malformations (EIEE1; 308350) to nonsyndromic mental retardation (300419). Although males with ARX mutations are often more severely affected, female mutation carriers may also be affected (Kato et al., 2004; Wallerstein et al., 2008). |
| Miscellaneouse | N/A |
| Prevalence | Prevalence: <1/1000000 (Worldwide) [source: MalaCards] |
| Inheritance | X-linked recessive |
| Anticipation | Yes |
| Evidence | Strong |
| Gene symbol | ARX |
| Alias symbols | SSX; PRTS; CT121; EIEE1; MRX29; MRX32; MRX33; MRX36; MRX38; MRX43; MRX54; MRX76; MRX87; MRXS1 |
| Gene name | aristaless related homeobox |
| Gene map locus | Xp21.3; chrX:25,003,694-25,016,420(-) |
| Ensembl Gene ID | ENSG00000004848 |
| Gene expression and Gene Ontology | BioGPS |
| Protein expression | Human Protein Atlas |
| Gene sequence | Sequence |
| Variation | ClinVar, dbSNP | Gene conservation | Gene Conservation from UCSC Genome Browser |
| Gene Description | This gene is a homeobox-containing gene expressed during development. The expressed protein contains two conserved domains, a C-peptide (or aristaless domain) and the prd-like class homeobox domain. It is a member of the group-II aristaless-related protein family whose members are expressed primarily in the central and/or peripheral nervous system. This gene is thought to be involved in CNS development. Expansion of a polyalanine tract and other mutations in this gene cause X-linked mental retardation and epilepsy. [provided by RefSeq, Jul 2016] |
| Repeat unit | GCG |
| Normal repeat copies | 12 |
| Pathogenic repeat copies | ≥20 |
| Gene | ARX |
| Repeat location | CDS |
| Chromosome locus | chrX:25013653-25013691 (-) |
| Repeat conservation | Repeat Conservation from UCSC Genome Browser |
| Toxic cause | Protein |
| Possible toxicity | The same likely applies to our patients, in whom cellular neuropathology caused by the PolyA expansion is presumably present at birth and causes early infantile spasms but only produces dyskinesia later, when the anatomic substrate becomes functionally expressed. [By PMID: 17664401] |
| Pathway annotation | Reactome, KEGG |
| PMID | 12376949 |
| Authors | Frints SG, Froyen G, Marynen P, Willekens D, Legius E, Fryns JP |
| Title | Re-evaluation of MRX36 family after discovery of an ARX gene mutation reveals mild neurological features of Partington syndrome |
| Journal | Am J Med Genet. 112(4):427-8 |
| Year | 2002 |
| PMID | 21204215 |
| Authors | Cossée M, Faivre L, Philippe C, Hichri H, de Saint-Martin A, Laugel V, Bahi-Buisson N, Lemaitre JF, Leheup B, Delobel B, Demeer B, Poirier K, Biancalana V, Pinoit JM, Julia S, Chelly J, Devys D, Mandel JL |
| Title | ARX polyalanine expansions are highly implicated in familial cases of mental retardation with infantile epilepsy and/or hand dystonia |
| Journal | Am J Med Genet A. 155A(1):98-105 |
| Year | 2011 |