In adolescents, fasting insulin (in Mu/L) and waist circumference (WC) have most strongly been associated with parameters of obesity and homeostatic model assessment-insulin resistance (HOMA-IR) levels have been shown to be increased with increase in BMI and within each BMI category—higher body fat was associated with higher HOMA-IR [5, 6]. This evidence concerns the gene INS and obesity due to melanocortin 4 receptor deficiency.