Given that there is an inverse relationship between serum leptin levels and BE incidence in women, despite higher levels of serum leptin than those in men, it is assumed that other factors, such as sex hormones, may contribute to sex differences in the incidence of esophageal diseases, including esophageal adenocarcinoma, which have a strong male predominance [1,64]. The gene discussed is LEP; the disease is Barrett esophagus.