Dunedin cohort genotyping was conducted with a commercially available array (BeadPlex Array; Illumina Inc.) using DNA extracted from whole blood (93% of the sample) or buccal swabs (7% of the sample). GRS SNPs or proxies (linkage R2≥0.85) were called successfully in >95% of European-descent study members (Supplemental Table 1). These n=880 individuals formed the analysis sample. Cohort members carried an average of 7.06 of 12 possible risk alleles (SD=2.27). Cohort members’ sex and socioeconomic status39 were unrelated to their genetic risk (Pearson's r ≤0.01). The GRS was standardized to have mean=0 and standard deviation=1 for analyses (genetic risk Z-score).
