(12) explored the alanine (Ala) to valine (Val) polymorphism in exon 2 and the isoleucine to threonine polymorphism at codon 56 of the manganese superoxide dismutase gene (MnSOD) to further define the risk factors for bladder cancer with 213 patients and 209 normal controls. Here, SOD2 is linked to urinary bladder carcinoma.