Patients with obesity are leptin-resistant, which, in addition to inhibiting the hypothalamic-pituitary-testicular response to decreasing androgen levels, also directly inhibits testosterone production by suppressing the stimulation of Leydig cells by means of gonadotropins secreted in the arcuate nucleus of the hypothalamus [22,25]. The gene discussed is LEP; the disease is obesity due to melanocortin 4 receptor deficiency.