| Melanocortin 4 receptor (MC4R) deficiency is the commonest form of monogenic obesity identified so far. MC4R deficiency is characterized by severe obesity, an increase in lean body mass and bone mineral density, increased linear growth in early childhood, hyperphagia beginning in the first year of life and severe hyperinsulinemia, in the presence of preserved reproductive function. MC4R is a G protein-coupled receptor involved in the hypothalamic leptin-melanocortin signalling pathway. Activation of the MC4R plays a key role in the maintenance of energy homeostasis and is associated with suppression of food intake. |
