Dong J, et al. - Using a 2-sample (summary data) approach, researchers conducted a Mendelian randomization study to determine the relationships between circulating concentrations of 25(OH)D and risks of esophageal adenocarcinoma (EAC) and its precursor, Barrett’s esophagus (BE). Data were collected from 6,167 BE patients, 4.112 EAC patients and 17,159 people without BE or EAC (controls) participating in the Barrett’s and Esophageal Adenocarcinoma Consortium, as well as studies from Bonn, Germany and Cambridge and Oxford, UK. No evidence was found for an association between genetically estimated 25(OH)D concentration and risk of BE or EAC. The odds ratio (OR) for EAC risk was 0.68, estimated by combining the individual single-nucleotide polymorphism (SNP) association using inverse variance weighting.