In the present study, we examined 5HT2A –1438G/A (rs6311), 5HT2C -759C/T (rs3813929) and COMT 24938 A/G (rs4680) in relation to obesity and related metabolic quantitative traits in a group of middle-aged men representing a very broad range of BMI. This evidence concerns the gene HTR2A and obesity due to melanocortin 4 receptor deficiency.