PON1 and breast cancer: For that reason, we conducted this study to accomplish the following goals: (1) examine the association between PON1 L55M and Q192R polymorphisms and the risk of BC in women in Guangxi province; (2) analyze associations between these polymorphisms and clinicopathological characteristics in BC patients to determine whether these variations are useful genetic markers of BC; (3) perform subgroup analysis based on menopausal status; (4) evaluate the association between the cooccurrence of both polymorphisms and the risk of BC; and (5) analyze linkage disequilibrium between the two SNPs.