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ATXN3 ataxin 3

Gene ID: 4287, updated on 21-Mar-2023
Gene type: protein coding
Also known as: AT3; JOS; MJD; ATX3; MJD1; SCA3


Machado-Joseph disease, also known as spinocerebellar ataxia-3, is an autosomal dominant neurologic disorder. The protein encoded by this gene contains (CAG)n repeats in the coding region, and the expansion of these repeats from the normal 12-44 to 52-86 is one cause of Machado-Joseph disease. There is a negative correlation between the age of onset and CAG repeat numbers. Alternatively spliced transcript variants encoding different isoforms have been described for this gene. [provided by RefSeq, Jul 2016]

Associated conditions

See all available tests in GTR for this gene

Azorean diseaseSee labs
Genetics of coronary artery calcification among African Americans, a meta-analysis.
GeneReviews: Not available
Genome wide study of maternal and parent-of-origin effects on the etiology of orofacial clefts.
GeneReviews: Not available
Identification of ten loci associated with height highlights new biological pathways in human growth.
GeneReviews: Not available
Many sequence variants affecting diversity of adult human height.
GeneReviews: Not available

Genomic context

Chromosome: 14; NC_000014.9 (92058552..92106582, complement)
Total number of exons:


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