English-language publications were included by searching the database - PubMed, ScienceDirect, EMBASE, using the terms - adolescent girls, PCOS, adipokines, leptin, adiponectin, resistin, apelin, vaspin, visfatin, ghrelin, omentin, obesity, insulin resistance, metabolic syndrome. The gene discussed is APLN; the disease is obesity due to melanocortin 4 receptor deficiency.