Association of promoter polymorphisms in the plasma glutathione peroxidase gene at the -723C/T locus with cerebral infarction

Abstract

Objective To investigate the relation between -723C/T single nucleotide polymorphisms (SNPs) of plasma glutathione peroxidase (GPX-3) gene promoter and cerebral infarction (CI).Methods By using a case-control method,102 patients with CI admitted to our hospital from February 2007 to February 2008 and 101 healthy subjects of Chinese Han populations of Western Guangdong were recruited in the study.The genotypes and alleles of-723C/T SNPs of GPX-3 promoter were analyzed by polymerase chain reaction and restriction fragment length polymorphism to investigate the distribution characteristics between the normal population and patients with CI; and the clinical data and stroke risk factors were compared between the 2 groups.Multivariate logistic regression was employed to analyze the risk factors of cerebral infarction,and stratified analysis was performed on these risk factors.Results The genotype frequencies of-723C/T in Western Guangdong Hart population were:CC 80.30％,CT 19.70％,respectively,and no genotype TT was found in this study.Allele frequencies were:C 90.15％,T 9.85％,respectively; the CC genotype frequency (86.27％) in patient group was higher than that in controls (74.26％),and the difference was significant (P=0.031); C allele frequency in patient group (93.14％) was higher than that in controls (87.13％),and the difference was also significant (P=0.042).By logistic regression analysis,the -723C/T genotype and history of hypertension and diabetes mellitus were the independent risk factors of CI.As compared with the subjects without carrying any risk factors or risk genotype,subjects carrying risk factors and CC genotype had significantly higher risk of CI (P＜0.05).Conclusion The -723 C/T SNPs ofGPX-3 gene promoter exists in Western Guangdong Chinese Han population; the C allele is a risk factor for CI; CC genotype may be the susceptible genotype with CI and the independent risk factor. Key words: Plasma glutathione peroxidase; Cerebral infarction; Gene promoter; Singlenucleotide polymorphism