The following results are derived from the cohort of non-diabetic individuals only (n = 3885). Table 4 shows obesity risk estimates (odds ratios; OR) for each of the genetic predictor variables ranked by magnitude of effect in non-diabetics. As with the BMI models reported above, the FTO rs1121980 variant was the most strongly associated SNP, with a per allele OR of 1.15 (95% CI 1.05–1.25; P = 0.0016). Five of the remaining SNPs (SH2B1, MTCH2, MC4R, NEGR1 and GNPDA2) were significantly associated with obesity in directions consistent with prior reports of association with BMI (6–8). For the GBS, the risk of obesity increased by 1.13 (95% CI 1.06–1.21; P = 0.0002) per SD unit increase, with a 1.40-fold (95% CI 1.14–1.72; P = 0.002) increased risk of being obese for those in the top compared with the bottom quintiles of the score. One SNP (MC4R rs17782313) statistically interacted with sex (P = 0.02), whereby the minor allele was associated with increased obesity risk in women (OR = 1.20; 95% CI 1.06–1.36; P = 0.0034), but no effect was observed in men (OR = 0.94; 95% CI 0.79–1.12; P = 0.48).
