Maternal overnutrition has been shown to alter circulating leptin levels and gene expression of key hypothalamic appetite regulators, such as neuropeptide Y (NPY) and pro-opiomelanocortin (POMC), on P1, one day after birth [18], suggesting that the influences of maternal diet on the establishment of hypothalamic satiety signalling take place during intrauterine development. The gene discussed is NPY; the disease is overnutrition.