Melanotan What It Is and Its Relation to Skin Cancer Who's tan is reay for summer. This peptide can help. Your body already makes a hormone that tells your skin to tan. Melanotan 2 is a synthetic peptide engineered to mimic that hormone but in a version that's more potent and Your body already makes a hormone that tells your skin to tan. Melanotan 2 is a synthetic peptide engineered to mimic that hormone but in a version that's more potent and Change in moles linked to use of unlicensed sun tan jab The BMJ