The risk of developing cholelithiasis was significantly associated with lower total hemoglobin level (SMD = −0.45; P = 0.002), lower hemoglobin F (HbF) level (SMD = −0.85; P = 0.003), higher total serum bilirubin level (SMD = 1.15; P < 0.001), higher reticulocytes count (SMD = 0.44; P = 0.007), and UDP‐glucuronosyltransferase‐1A1 enzyme (UGT1A1) promoter polymorphism. The gene discussed is UGT1A1; the disease is cholelithiasis.