Objective: To study the association between the variation of beta fibrinogen gene promoter -455G/A and ischemic stroke.
Methods: Eighty-six hypertensive patients with ischemic stroke (stroke group) and 85 hypertensive patients without ischemic stroke (hypertensive group) were randomly selected from the in patients, and 90 healthy persons(control group) were recruited for this study. Polymerase chain reaction with restrictive enzyme Hae III (PCR-restriction fragment length polymorphism method) was employed to analyze the polymorphism of beta-fibrinogen gene promoter -455G/A. Plasma fibrinogen levels were measured with prothrombin time (PT) assay.
Results: A(-455) allele frequencies of the stroke group (0.22) was significantly higher than that of the control group and the hypertensive group (0.11, 0.13, chi-square=8.3 P<0.05). The genotype exhibited significant difference among the 3 groups; G/A and A/A were more commonly seen in the stroke group(chi-square=10.03,P<0.05). The mean fibrinogen level of the stroke group(4.82+/-0.26 g/L) was significantly higher than that of the control group and the hypertensive group(4.37+/-0.19, 5.50+/-0.20, F=5.98 P<0.01) In both stroke group and hypertensive group, the plasma fibrinogen levels in patients with -455G/G were significantly lower than those in patients with -455G/A, and -455A/A but the difference was not significant among the 3 genotypes in the control group.
Conclusion: Plasma fibrinogen level could be affected by the beta-fibrinogen gene -455G/A polymorphism. And A(-455) allele may be an independent risk factor for ischemic stroke.