On the genetic level, SNPs, particularly in the LEPR gene, are polymorphisms that contribute to the heredity of obesity and are risk factors for the development of PCOS; on the other hand, maternal obesity exerts adverse epigenetic effects, e.g., on the LEP gene, which can be transferred to the fetus and might contribute to the adiposity of the child and might later affect PCOS risk. The gene discussed is LEP; the disease is obesity due to melanocortin 4 receptor deficiency.