Previously, several studies have revealed that metabolic diseases such as obesity, diabetes, dyslipidemia, hypothyroidism, and hyperthyroidism can lead to excessive oxidative stress in the testes, while melatonin can vigorously potentiate endogenous anti-oxidant defense by upregulating SOD, GSH, and GPx (30, 37, 49, 52, 62, 63). The gene discussed is SOD1; the disease is obesity due to melanocortin 4 receptor deficiency.