Our previous study14 gave new insights into the pleiotropic role of leptin during foetal development at late gestation since leptin was found to be present in AF (from day 20 in our model, i.e. near term) and a potential relationship between placental leptin production and leptin levels in AF, foetal gastric content, and foetal stomach was suggested, with AF leptin probably contributing directly to foetal stomach leptin14. The gene discussed is LEP; the disease is atrial fibrillation.