OBJECTIVETo explore the distribution of fibrinogen (FGB) B beta polymorphism in Chinese Han population and the association of the polymorphisms with the occurrence of atherosclerotic cerebral infarction (ACI).

METHODSThe B beta gene FGB -455G/A polymorphism was identified by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) in 132 patients with ACI and 148 healthy controls matching on age and sex. Turbidimetric assays were performed to measure the plasma fibrinogen levels of all cases.

RESULTSThe plasma fibrinogen level in ACI group (3.42+/-0.52 g/L), was significantly higher than that in the controls (2.96+/-0.42g/L), P<0.001. The A allele was associated with the elevated plasma fibrinogen levels in both patients and controls. Among the A allele carriers, smokers had significantly higher plasma fibrinogen levels than did the non-smokers (P<0.05). The distribution of B beta gene FGB -455G/A polymorphism was in accordance with the Hardy-Weinberg equilibrium (P>0.05). The A allelic frequency in ACI group (0.258) was significantly higher than that in the control group (0.152) (P<0.05). Logistic regression analysis showed that the cases carrying A allele (GA+AA genotype) had 1.653 times the risk of ACI.

CONCLUSIONThe study demonstrates that A allele of the B beta gene FGB -455G/A polymorphism may be a susceptible predictor of the occurrence of ACI, particularly in smokers.