XRCC1 and cancer: X-Ray Repair Cross-Complementing Group 1 (XRCC1), located on 19q13.2, is a polymorphic BER gene that has been the most extensively examined in molecular epidemiologic studies of the risk of various cancers.30 In the above-mentioned population-based case–control study conducted in 6 areas of San Francisco Bay,31 a synergistic effect between the XRCC1 399Gln allele and tobacco smoking in relation to pancreatic cancer risk was observed, although no significant associations were noted between XRCC1 genotypes and pancreatic cancer risk.