Influence of Transforming Growth Factor-β1 Gene Polymorphism at Codon 10 on the Development of Cirrhosis in Chronic Hepatitis B Virus Carriers

Transforming growth factor (TGF)-beta 1 is a key cytokine producing extracellular matrix. We evaluated the effect of TGF-beta 1 gene polymorphism at codon 10 on the development of cirrhosis in patients with chronic hepatitis B. One hundred seventy eight patients with chronic hepatitis (CH, n=57) or liver cirrhosis (LC, n=121), who had HBsAg and were over 50 yr old, were enrolled. The genotypes were determined by single strand conformation polymorphism. There were no significant differences in age and sex ratio between CH and LC groups. HBeAg positivity and detection rate of HBV DNA were higher in LC than in CH groups (P=0.055 and P=0.003, respectively). There were three types of TGF-beta 1 gene polymorphism at codon 10: proline homozygous (P/P), proline/leucine heterozygous (P/L), and leucine homozygous (L/L) genotype. In CH group, the proportions of P/P, P/L, and L/L genotype were 32%, 51%, and 17%, respectively. In LC group, the proportions of those genotypes were 20%, 47%, and 33%, respectively. The L/L genotype was presented more frequently in LC than in CH groups (P=0.017). Multivariate logistic regression analysis confirms that detectable HBV DNA (odds ratio [OR]: 3.037, 95% confidence interval [CI]: 1.504-6.133, P=0.002) and L/L genotype (OR: 3.408, 95% CI: 1.279-9.085, P=0.014) are risk factors for cirrhosis.