Relationship between hOGG1 Ser326Cys gene polymorphism and coronary artery lesions in patients with diabetes mellitus.

To study the relationship between human 8-oxoguanine glycosylase (hOGG1) Ser326Cys gene polymorphism and coronary artery lesions in patients with diabetes mellitus, we analyzed 323 patients with diabetic mellitus, who underwent coronary angiography. Using PCR-RFLP, these patients were grouped into three genotypes: Cys/Cys (n=85), Ser/Ser (n=121), and Ser/Cys (n=117). Several clinical data, including history of diseases and biochemical indices were recorded. hOGG1 mRNA expression and 8-hydroxy deoxyguanosine (8-OHdG) were measured by RT-PCR and ELISA, respectively. The quantities and severity of coronary artery with lesions were analyzed from coronary angiography. The Gensini and SYNTAX scores were detected by the unitary criteria. The 8-OHdG levels showed statistical difference among the three genotypes (F=21.56, P<0.05). Also, 8-OHdG in Cys/Cys genotype was higher than Ser/Ser and Ser/Cys genotype (q=2.32, q=3.12, P<0.05). In terms of the expression of hOGGl mRNA, the measure of hOGGl/β-actin showed significant difference among the three groups (F=12.56, P<0.05). On comparing two groups, hOGGl/β-actin in Cys/Cys genotype was higher thanSer/Ser and Ser/Cys genotypes (q=2.32, q=3.12, P<0.05). Percentage of 3-vessel lesions was high in Cys/Cys genotype and percentage of 1-vessel lesions was low in Ser/Cys genotype. Gensini and SYNTAX scores and ratio of complex lesions were significantly higher in the Cys/Cys genotype than the other two genotypes (FGensini=47.16, FSYNTAX=55.12; P<0.05). hOGG1 Ser326Cys polymorphism showed correlation with coronary artery lesions in patients with diabetes mellitus, and Cys/Cys genotype may have more impact on the severity of lesions.