We analyzed GERA samples (see URLs; dbGaP study accession phs000674.v1.p1) typed on each of the four GERA ancestry-specific chips (European, African, East Asian, and Latino); QC is described in ref.23. We directly analyzed all samples and all autosomal SNPs in each of the four sub-cohorts (Supplementary Table 1). We identified independent trios in each sub-cohort according to pedigree information provided with the data release.
