Association of polymorphic markers of the catalase and superoxide dismutase genes with type 2 diabetes mellitus.

Our study aims at determining whether genetic polymorphisms of catalase (CAT 1167C/T) and superoxide dismutase (SOD +35 A/C) could be associated with type 2 diabetes mellitus (T2DM). The study was conducted on 105 Egyptian patients with T2DM and 115 control subjects. Genotypes were done by polymerase chain reaction-restriction fragment length polymorphism methods. Homeostatic model assessment of insulin resistance (HOMA-IR), CAT and SOD activities, glycated hemoglobin, and insulin and lipid profiles were assessed. CAT and SOD activities were significantly decreased in T2DM compared with the control subjects. T allele of CAT and C allele of SOD1 were significant risk factors for T2DM. No effects of CAT or SOD1 gene polymorphisms on glycated haemoglobin or on HOMA-IR were found. With regard to the enzymes activities, only +35 A/C of SOD1 was related to SOD activity. Genetic variants C1167T of CAT gene and +35 A/C of SOD1 gene has no role in insulin resistance in T2DM.