XRCC1 and colonic neoplasm: With regard to the XRCC1 194Trp allele, a large case-control study in the United States reported that this allele was associated with a modest increase in the risk of colon cancer,11 while another study showed that it had an insignificant modifying effect on the association between alcohol consumption and risk.16 However, most studies found that the 194Trp allele was not associated with an increased risk of colorectal cancer,9,12,14–16 and the present study observed no association between the Arg194Trp polymorphism and risk.