Two novel variants on 13q22.1 are associated with risk of esophageal squamous cell carcinoma
A partir de données d'une étude d'association sur le génome entier portant sur 2 031 cas, 2 044 témoins et 5 930 polymorphismes à simple nucléotide, cette étude identifie deux nouveaux variants sur la région du chromosome 13q22.1 associés au risque de carcinome épidermoïde de l'œsophage
Background:Chromosome 13q22.1 has previously been identified to be a susceptibility locus for pancreatic cancer in Chinese and European ancestry populations. This pleiotropy study aimed to identify novel variants in this region associated with susceptibility to different types of human cancer. Methods:To fine-map the 13q22.1 region, imputation analyses were conducted based on the GWAS data of 2,031 ESCC cases and 2,044 controls and 5,930 SNPs (625 directly genotyped and 5,305 well-imputed). Promising associations were then examined in esophageal squamous cell cancer (ESCC) (4,146 cases and 4,135 controls), gastric cardia cancer (1,894 cases and 1,912 controls), non-cardia gastric cancer (1,007 cases and 2,243 controls) and colorectal cancer (1,111 cases and 1,138 controls). Fine mapping and biochemical analyses were further performed to elucidate the potential function of novel variants. Results:Two novel variants, rs1924966 and rs115797771, were associated with ESCC risk (P=1.37×10-10 and P=2.32×10-10, respectively) and were also associated with risk of gastric cardia cancer (P=0.0003 and P=0.0018, respectively) but not gastric cancer and colorectal cancer. Fine-mapping revealed another SNP, rs58090485, in strong linkage disequilibrium with rs115797771 (r2=0.94). Functional analysis showed that this SNP disturbs a transcriptional repressor binding to the promoter region of KLF5, which might result in high constitutional expression of KLF5. Conclusions:These results demonstrate that variants mapped on 13q22.1 are associated with the risk of different types of cancer. Impact:13q22.1 might serve as a biomarker for the identification of individuals at risk for ESCC and gastric cardia cancer.