DNA was purified from cerebellar tissue or peripheral blood lymphocytes with DNeasy columns (Qiagen, Valencia, CA). All SNP assays were obtained as Taqman Assays-On-Demand (Applied Biosystems, Foster City, CA) and genotyping was performed according to the manufacturer’s protocol. Genotype was determined in triplicate using an ABI 7900HT available in the Mount Sinai Quantitative PCR Shared Resource Facility.
