APOA5 and obesity due to melanocortin 4 receptor deficiency: As Corella reported in 2007, they examined the interaction between the -1131 T > C and c.56C > G (S19 W) of APOA5 SNPs and the nutrient intake (total fat, carbohydrate, and protein) in their relation to the BMI and obesity risk in 1073 men and 1207 women participating in the Framingham Offspring Study.