XRCC1 and non-small cell lung carcinoma: Remarkably, XRCC1 -77T > C was identified as functional polymorphism, diminishing promoter activity and thus increasing the risk of non-small cell lung cancer (NSCLC), while the three non-synonymous XRCC1 SNPs R194W, R280H and R399Q, whose functional characteristics are not determined yet, showed no association with NSCLC risk [15].