Genotyping of the 10 SNPs was conducted using DNA extracted from buccal cells collected at the phase 21 Fast Track follow-up using a cytology brush. DNA extraction was performed by Penn State University. Samples were then shipped to the Virginia Institute for Psychiatric and Behavioral Genetics for genotyping. Genotyping was conducted using commercially available primer and probe sequences from TaqMan Assays-on-Demand (Applied Biosystems, Foster City, CA). Duplicate genotyping produced concordance rates of 100 percent. For samples passing quality control (genotyping success rate of >80 percent), call rates for the 10 NR3C1 SNPs ranged from 87 percent to 99 percent. All SNPs were in Hardy-Weinberg equilibriumx (minimum p-value>0.2 for European-American and African-American samples).
