[Correlation between polymorphism of TaqI of ET-1 gene and cirrhotic portal hypertension].

OBJECTIVE

To investigate the correlation between polymorphism of TaqI of endothelin (ET)-1 gene intron 4 and cirrhotic portal hypertension and to search new risk factor of portal hypertension.

METHODS

Peripheral venous blood was extracted from 106 patients with cirrhosis after hepatitis B (PH+ group) and 108 healthy blood donors (PH- group). PCR-RFLP was used to analyze the polymorphism of TaqI of ET-1 gene. The plasma ET-1 concentration was detected with immunoassay. Multivariate logistic regression analysis was made to analyze the risk factors.

RESULTS

The C allele frequency in the PH+ group was 25.4%, significantly higher than that of the controls (16.7%, P < 0.05). The frequency of CC + TC genotype in PH+ group was 46.2%, significantly lower than that in the controls (29.6%, P < 0.05). In the PH+ group, the thickness of spleen was greater, hemorrhage rate was higher, and III degrees ascites was more in C allele carrier than in T allele carriers (P < 0.05). The plasma ET-1 concentration was higher in PH+ group than in PH- group. In the PH+ group, the plasma ET-1 concentrations in those with CC genotype and those with TC genotype were significantly higher than in those with TT genotype (P < 0.05). Correlation analysis showed that ET-1 gene polymorphism was positively correlated with plasma ET-1 concentration (R = 0.808 2). Multivariate logistic regression analysis showed that gradation of liver function, diameter of portal vein, and ET-1 gene polymorphism were independent risk factors of portal hypertension.

CONCLUSION

Polymorphism of TaqI of ET-1 gene is correlated with the pathogenesis of cirrhotic portal hypertension. It may be one of the risk factors of portal hypertension.