Ten NR3C1 single nucleotide polymorphisms (SNPs) were selected for genotyping with the aim of optimizing the degree of genetic sequence variability accounted for by the fewest number of SNPs. There are many common DNA sequence variants within the NR3C1 gene. Clusters of these variants are in linkage disequilibrium (LD; inherited together and therefore non-independent). We used a reference database (HapMap version 3; http://hapmap.ncbi.nlm.nih.gov/) to identify variants that tagged independent clusters of variants (Dick et al. 2011). The 10 SNPs identified through this tagging procedure were at least partially independent in the current samples: maximum linkage disequilibrium as measured by R2 equal to 0.56 (EA) and 0.53 (AA) (see Supplementary Figure 2). Genotyping of the 10 SNPs was conducted using DNA extracted from buccal cells collected at the phase 21-year-old 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
