Hormones that may be possibly related to ED are androgens (testosterone = T, dihydrotestosterone = DHT, androstenedione, dehydroepiandrosterone = DHEA and dehydroepiandrosterone-sulphate = DHEA-SO4), estrogens (in particularly, estradiol = E2), insulin (cause of DM and consequently, an indirect cause of ED), thyroid hormones, prolactin (PRL), melatonin, leptin and growth hormone (GH). The gene discussed is GH1; the disease is diabetes mellitus.