Objective To determine whether the paraoxonase2 (PON2) gene A148G polymorphism is associated with the pathogenesis of nephropathy in type 2 diabetes mellitus patients (DN) . Methods PON2 genotype distribution and allele frequency were examined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) . Serum immune reactive insulin (IRI) and C-peptide (C-P) concentrations were measured by radioimmunity. Results GG genotype and G allele frequency were higher in DN group than that in simple type 2 diabetes mellitus group (x2 =4. 26 P