Expression QTL-based analyses reveal the mechanisms underlying colorectal cancer predisposition.

Genome-wide association studies have identified many risk loci associated with colorectal cancer. Strategies integrating biological data sets with GWAS results will provide insights into the roles of risk single-nucleotide polymorphisms. We performed expression quantitative trait locus-based analyses using the information provided in The Cancer Genome Atlas. Analysis of the cis-expression quantitative trait loci (eQTLs) of 18 previously reported colorectal cancer risk loci resulted in the discovery of five variants that were significantly associated with gene expressions. Analysis of the trans-eQTLs identified three risk loci that affect the expression levels of a neighboring transcription factor, MYC. These findings provide a more comprehensive picture of gene expression determinants in colorectal cancer and insights into the underlying biology of risk loci.