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Evaluating the prevalence of polyglutamine repeat expansions in amyotrophic lateral sclerosis.

ABSTRACT:

Objective

Given the recent finding of an association between intermediate-length polyglutamine (polyQ) expansions in ataxin 2 and amyotrophic lateral sclerosis (ALS), we sought to determine whether expansions in other polyQ disease genes were associated with ALS.

Methods

We assessed the polyQ lengths of ataxin 1, ataxin 3, ataxin 6, ataxin 7, TBP, atrophin 1, and huntingtin in several hundred patients with sporadic ALS and healthy controls.

Results

Other than ataxin 2, we did not identify a significant association with the other polyQ genes and ALS.

Conclusions

These data indicate that the effects of ataxin 2 polyQ expansions on ALS risk are likely to be rooted in the biology of ataxin 2 or ataxin 2-specific interactions, rather than the presence of an expanded polyQ repeat per se. These findings have important consequences for understanding the role of ataxin 2 in ALS pathogenesis and provide a framework for future mechanistic studies.

SUBMITTER: Lee T

PROVIDER: S-EPMC3111240 | biostudies-literature |

REPOSITORIES: biostudies-literature

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