Recently, a study by Park et al. in Chinese population have evaluated the variations in hormone receptors (ESR1, ESR2) in relation to biliary tract cancers (35) and reported an association with ESR1 (rs1801132) and ESR2 (rs1255953) variants in GBC risk, but we did not observe any significant association with these exonic polymorphisms. The gene discussed is NR4A1; the disease is biliary tract cancer.