MC4R and obesity due to melanocortin 4 receptor deficiency: To understand whether the previous data were biased by not strict selection criteria in patients recruitment, we have screened MC4R in a group of Italian obese children selected, with a multicentric approach, on the basis of their phenotype (i.e.; familiar history of obesity, BMI ≥ 3 deviation scores, obesity onset before the 10 years old, height ≥ 2 deviation scores).