ABCB1/4 gallbladder cancer risk variants identified in India also show strong effects in Chileans
Background: The first large-scale genome-wide association study of gallbladder cancer (GBC) recently identified and validated three susceptibility variants in the ABCB1 and ABCB4 genes for individuals of Indian descent. We investigated whether these variants were also associated with GBC risk in Chileans, who show the highest incidence of GBC worldwide, and in Europeans with a low GBC incidence. Methods: This population-based study analysed genotype data from retrospective Chilean case-control (255 cases, 2042 controls) and prospective European cohort (108 cases, 181 controls) samples consistently with the original publication. Results: Our results confirmed the reported associations for Chileans with similar risk effects. Particularly strong associations (per-allele odds ratios close to 2) were observed for Chileans with high Native American (=Mapuche) ancestry. No associations were noticed for Europeans, but the statistical power was low. Conclusion: Taking full advantage of genetic and ethnic differences in GBC risk may improve the efficiency of current prevention programs. ; Federal Ministry of Education & Research (BMBF) 01DN15021 European Union (FP7 Research infrastructures) within the initiative "Biobanking and Biomolecular Research Infrastructure -Large Prospective Cohorts" (Collaborative study "Identification of biomarkers for gallbladder cancer risk prediction Towards personali Germany's Excellence Initiative of Heidelberg University within the program "Mobilitaetsmassnahmen im Rahmen internationaler Forschungskooperationen 2015-16" support program "Stiftungen und Preise" of the Ruprecht-Karls-Universitaet Heidelberg German Research Foundation (DFG) LO 2061/1 Biobank of University of Chile