XRCC1 and breast cancer: As shown in table 3, the level of statistical significance of beta coefficients was particularly high for the association between BC risk and, on the other hand, packyears (beta  = 0.256; p<0.001) and coffee (beta  = 0.166; p<0.001); as well as for the association between decreased DNA adduct and XRCC1 Arg 399 (beta  = −0.129; p<0.006).