In addition to promoting growth, increases in these hormones have been reportedto stimulate adipogenic activity and adipocyte differentiation(18), thereby increasing susceptibility to overweight and obesity at a later age.However, to date, a few studies have evaluated the effects of formulae that differ only intheir protein content on IGF-1 concentration in infants. The gene discussed is IGF1; the disease is obesity due to melanocortin 4 receptor deficiency.