KRAS and colorectal carcinoma: Participants with the variant CTH rs1021737 genotype had a decreased risk of KRAS-mutated CRC (OR per allele = 0.72, 95% CI = 0.50, 1.05), and an increased risk of BRAF-mutated CRC (OR = 1.56, 95% CI = 1.07, 2.30), but with weak evidence for heterogeneity (Pheterogeneity = 0.01).