Fifty-six variants catalogued from two large-scale BMI meta-analyses were used to construct the GRSS (Thorleifsson et al. 2009; Willer et al. 2009). These variants were summarized in the GRSS which was calculated by summation of the number of risk alleles across the SNPs for each individual divided by the number of SNPs in the score to achieve an average allele count. The frequencies of GRSSs are shown in Fig. 1 and produced a relatively normal distribution. The mean GRSS, or average number of risk alleles present per locus, was 0.494 (SD = 0.052) with a range from 0.318 to 0.691 which corresponds to an average of 55 risk alleles per person with a range from 35 to 77.
