Genotyping was conducted using the custom Illumina Infinium array (iCOGS) (14 (link)). DNA samples containing each of the variants were included in iCOGS genotyping as positive controls and were used to inform genotype calling. Genotypes were called with the GenCall algorithm. Descriptions of sample and genotype quality control have been published (14 (link), 16 (link)). Cluster plots for rare variants for this study were manually evaluated relative to positive control samples.