Article

Association of Long ATXN2 CAG Repeat Sizes With Increased Risk of Amyotrophic Lateral Sclerosis

Centre for Excellence in Neuromics, CHUM Research Center, Université de Montréal, 2099 Alexandre De-Seve St, Montreal, QC H2L 2W5, Canada.
Archives of neurology (Impact Factor: 7.58). 06/2011; 68(6):739-42. DOI: 10.1001/archneurol.2011.111
Source: PubMed

ABSTRACT To analyze the ataxin 2 (ATXN2) CAG repeat size in a cohort of patients with amyotrophic lateral sclerosis (ALS) and healthy controls. Large (CAG)(n) alleles of the ATXN2 gene (27-33 repeats) were recently reported to be associated with an increased risk of ALS.
Case-control study.
France and Quebec, Canada.
A total of 556 case patients with ALS and 471 healthy controls; both groups of participants are of French or French-Canadian origin.
We observed a significant association between ATXN2 high-length alleles (≥29 CAG repeats) and ALS in French and French-Canadian ALS populations. Furthermore, we identified spinocerebellar ataxia type 2-pathogenic polyglutamine expansions (≥32 CAG repeats) in both familial and sporadic ALS cases.
Altogether, our findings support ATXN2 high-length repeats as a risk factor for ALS and further indicate a genetic link between spinocerebellar ataxia type 2 and ALS.

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