慢性HBV C基因启动子变异的检测

目的 了解慢性乙型肝炎病毒（ＨＢＶ）Ｃ基因启动子变异的情况以及对病毒血清学的影响。方法 应用错配聚合酶链反应特异性扩增含有ＨＢＶ Ｃ基因启动子的片段，扩增产物用限制性内切酶Ｂｃｌ Ｉ酶切，琼脂糖凝胶电泳后，观察酶切后的限制性片段长度多态性（ＲＦＬＰ）图谱，分析Ｃ基因启动子区段的核苷酸（ｎｔ）１７６２由碱基Ａ→Ｔ和（ｎｔ）１７６４碱基由Ｇ→Ａ的变异，并经直接测序分析证实ＲＦＬＰ结果。结果 １１０例慢

Detection of core promoter mutations in chronic hepatitis B

Objective To study the core promoter mutation in chronic hepatitis B and its effect on viral serology.Methods HBV core promoter gene fragments were amplified by using mismatched PCR combined with a restriction fragment length polymorphism assay. The PCR products were digested with BcL I and subjected to electrophoresis on agarose gels.Results We investigated the core promoter mutation in 89 patientswith HBV DNA positive. The patterns of restriction fragment length polymorphism (RFLP) of the core promoter gene were distinguished and verified by direct sequencing. The combined mutations of nucleotides (nt) 1762 and 1764 in the core promoter from A to T and G to A were detected in 47 individuats, 21 of 43 HBeAg positive patients and 26 of 46 anti HBe positive cases were found infected with this combined mutant. These two groups showed no significant difference (P>0.05).The combined mutation was found in 11 of the 15 patients with medium and severe chronic hepatitis. In 5 chronic hepatitis B patients with coexistence of wild type and mutant a tendency of superior accumulation of mutant was found.Conclusion This study suggests that the core promoter mutations commonly exist in chinese chronic hepatitis B patients. The mutation can only reduce the pre core mRNA transcribing efficiency, but can not discontinue the synthesis of HBeAg. The effect on serology in this mutation is different from that in pre core stop 28 mutation. The superior accumulation of mutations seems relating to the degree of chronic liver disease.