Indeed, early studies showed higher estradiol concentrations in young to middle-aged subjects with obesity compared to lean controls [29], and following studies reported the treatment of hypogonadal subjects with obesity with selective estrogen receptor modulators (SERM) or anti-aromatase inhibitors (AI) to be successful in stimulating the HPT axis and in achieving physiological T levels [30,31]. The gene discussed is ESR1; the disease is obesity disorder.