FTO and obesity due to melanocortin 4 receptor deficiency: By combining overweight DS and ODS groups and comparing them against the NODS group, there were increased frequencies of the GT, TT, GT + TT genotypes of FTO rs17917449 and the T allele in the overweight/ODS, with a higher risk of developing obesity compared to the NODS groups (p 0.005, 0.018, 0.0027, 0.0099; OR 4.111, 9.0, 4.448, 2.139) (Table 2).