一种新的乙型肝炎病毒X基因变异方式  

A new mutation pattern of hepatitis B virus X gene

作　　者：肖鸿敏[1] 任建林[1] 毛乾国 许鸿志[1] 陈美娅[1] 张志平[1] 周飞[1] 潘金水[1] 蔡稼燕[1] 董菁[1] 

机构地区：[1]厦门大学附属中山医院消化内科福建医科大学教学医院(厦门大学附属中山医院)厦门大学消化疾病研究所厦门市消化疾病中心,福建省厦门市361004 [2]厦门中医院肝病三科,福建省厦门市361004

出　　处：《世界华人消化杂志》2008年第24期2695-2701,共7页World Chinese Journal of Digestology

基　　金：厦门市首批重大疾病科研攻关资助项目;No.WKZ0501;厦门市卫生局医学科研立项资助项目;No.WSK0506;厦门大学引进人才科研启动基金资助项目;No.Z03109;福建省青年科技人才创新资助项目;No.2006F3127~~

摘　　要：目的:证实乙型肝炎病毒(hepatitis Bvirus,HBV)X基因一种新的变异方式.方法:从HBV慢性感染患者血清中提取HBVDNA,扩增X基因序列,克隆入pMD19T载体,选择阳性克隆进行DNA测序,与已知HBV基因相应序列比较该患者体内HBV基因变异位点以及变异形式.结果:从21例患者中共挑选74个克隆测序,测序结果提示54个克隆X基因下游大段缺失突变,长度达234nt,位于1601-1834nt处,另有1个克隆发生245nt缺失突变.发生缺失变异的病毒株同时存在G/A1515C、G1518C和A1585T替换突变,这两种突变具有联动特征.缺失突变株HBx仅编码76aa,其第44和45位编码为LL,具有特异性.结论:观察到一种X蛋白变异方式,这种大段缺失突变导致X蛋白下游编码序列丢失,其为X因子还是X蛋白以及这种变异是否为常态形式尚需进一步研究.AIM： To identify a novel X gene mutation pattern of hepatitis B virus （HBV） in patients with chronic HBV infection,METHODS： A pair of primers was designed on the basis of nucleotide sequences of X gene. Polymerase chain reaction （PCR） was used to amplify the target region from HBV DNA samples extracted from chronic hepatitis B patients in Xiamen city. After electrophoresis of the PCR products in 9 g/L agarose gel, the target regions were cut, re-purified and TA-cloned into pMD19 T vector. The inserted regions in positive clones were sequenced. Sequence comparison with HBV genome submitted in GenBank was made to find the mutation sites. RESULTS： Totally 74 strains from 21 patients with chronic HBV infection were sequenced, and the results showed that there was a characteristic deletion region, with a length of 234 nt （nt 1601-1834） in 54 clones, and a length of 245 nt in I clone. There were 3 replacement mutations bounding to deletion mutation： G/A1515C, G1518C and A1585T, which caused substitutions in the 44th and 45th amino acid site to LL. These mutant strains only coded 76 aa of up-stream HBx. CONCLUSION： A novel deletion mutation in HBV X gene is observed in patients with chronic HBV infection. The deletion mutants encode 76-aa X factor instead of X protein.

关 键 词：乙型肝炎病毒 缺失突变 X因子 

分 类 号：R512.62[医药卫生—内科学]