Evidence for the GluR6 gene associated with younger onset age of Huntington's disease

Huntington's disease (HD) is attributed to a triplet. CAG repeat mutation, and about half of the variation in onset age can be explained by the size o f the repeat expansion. Recently, a TAA repeat polymorphism in close linkag e to the kainate receptor, GluR6, was reported related to onset age in HD. We examined this polymorphism in 258 unrelated HD-affected persons (172 fro m a clinic sample and 86 from a postmortem series). This study confirms tha t the 155 allele is associated with younger onset age of HD and suggests th at it is in linkage disequilibrium with a variant of the GluR6 gene or anot her gene in this region.