In a large nested case–control study based on the European Prospective Investigation into Cancer and Nutrition (EPIC), no association was reported between serum leptin and risk of colorectal cancer regardless further adjustment for BMI (RR: 0.85 (95% CI: 0.56–1.29) for the highest quintile compared to the lowest; Ptrend = 0.76) 10. The gene discussed is LEP; the disease is colorectal cancer.