The FTO SNP (rs1121980) was also strongly associated with total, abdominal and gynoid adipose mass (Table 3). As in earlier studies (3), the per allele increase in weight for FTO rs1121980 was 1.03 kg (P = 0.005), of which 0.91 kg was attributable to increased total adipose mass (P = 0.0007). As shown in Table 3, although trends for association with measures of adiposity were evident for several of the remaining SNPs in directions consistent with the associations with obesity, only three reached a formal level of statistical significance (FTO, MTCH2 and GNPDA2). Figure 1 shows the absolute weight difference between major and minor allele homozygotes at each of the obesity-associated loci and between the first and fifth quintiles of the genetic burden score (GBS). The figure also illustrates how much of the total weight difference between genotypes at a given locus is attributable to adipose accumulation. When the overall contribution of these SNPs was assessed using the GBS, strong associations were evident for all anthropometric (Fig. 2A and B) and dual-energy X-ray absorptiometry (DEXA) measures of obesity (Fig. 2C–E).
