NOS3 and obesity due to melanocortin 4 receptor deficiency: When this was done, the OR for the interaction term for obesity and the NOS3 G894T TT genotype in whites was 1.71 (95% confidence interval (CI) = 1.02–2.87) and the p-value for interaction was 0.042, only slightly changed from the values found when these study subjects were included (Table 3).