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.
出处
《世界华人消化杂志》
CAS
北大核心
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~~