Genotyping for the SNPs SOD2 A16V (rs4880), CAT −844 G>A (rs769214), and GPx1 rs1800668 C>T was carried out by real-time PCR allelic discrimination in a 7500 Fast Real-Time PCR instrument (Applied Biosystems, Foster City, California, USA), using Predesigned TaqMan SNP Genotyping Assays (Applied Biosystems; assay ID: C_1202883_20, C_850486_20, C_2548962_20). Reaction conditions and thermal profile were the same reported by Gugliandolo and coworkers .