关键词: 慢性乙型肝炎, 肿瘤坏死因子α, 基因多态性

Abstract: Objective To investigate the polymorphisms of promoter at -238 and -308 of necrosis factor-α gene in patients with HBeAg-positive chronic hepatitis B. Methods 203 HBeAg-positive chronic hepatitis B patients were recruited and the polymorphisms in TNF-α promoter at positions -238 and -308 were determined by polymerase chain reaction-restriction fragment length polymorphism assay，and the serum levels of TNF-α were examined by ELISA. Results The frequencies of TNF-α-238G/G and G/A genotypes were 84.7% and 15.3%， respectively，and the frequencies of TNF-α-308G/G，G/A and A/A genotypes were 76.8%，22.7% and 0.5%， respectively；The levels of TNF-α in patients with TNF-α-238G/A genotype were significantly lower than in those with G/G genotype（201.2±36.3 pg/ml vs 215.7±34.7pg/ml），（x2=4.355，P=0.037），and the levels of serum TNF-α in patients with -308G/A genotype were significantly higher than in those with G/G genotype（234.6±37.5pg/ml vs 207.4±32.3 pg/ml），（x2=14.653，P＜0.001）. Conclusion Higher levels of serum TNF-α are found more often in patients with TNF-α-238G/G or -308G/A genotypes.

Key words: Chronic hepatitis B, Tumor necrosis factor-α, Gene polymorphism