福建省慢性HBV感染者HBV基因S区、基本核心启动子区和前C区基因变异特征分析  

Genetic Mutations of the Hepatitis B Virus Genome S and BCP/Pre-C Regions of the Hepatitis B Virus(HBV)Genome in Chronic HBV Infection in Fujian Province of China

作　　者：李东[1] 杨秀惠[1,2] 陈致飞[1] 张苏晗 郑凝旋 潘伟毅[1,2] 周勇 郑奎城[1,2] LI Dong;YANG Xiuhui;CHEN Zhifei;ZHANG Suhan;ZHENG Ningxuan;PAN Weiyi;ZHOU Yong;ZHENG Kuicheng(Fujian Provincial Key Laboratory of Zoonosis Research, Fujian Center for Disease Control and Prevention, Fuzhou 350001, China;Teaching Base of Public Health School of Fujian Medical University, Fuzhou 350001, China)

机构地区：[1]福建省疾病预防控制中心、福建省人兽共患病重点实验室,福州350001 [2]福建医科大学公共卫生学院教学基地,福州350001

出　　处：《病毒学报》2018年第4期491-497,共7页Chinese Journal of Virology

基　　金：国家科技重大专项(项目号:2012ZX10002001-002-002),题目:艾滋病和病毒性肝炎等重大传染病防治;国家科技重大专项(项目号:2017ZX10103008-004),题目:浙江及周边省传染病病原谱流行规律研究——五大症候群病原谱监测~~

摘　　要：为研究福建省慢性HBV感染者HBV基因多样性及变异规律,了解该人群HBV-DNA的病毒学特征。收集慢性HBV感染者血清标本,通过巢式PCR法扩增其HBV基因序列,比对NCBI数据库中标准基因型序列,分析HBV基因S区,基本核心启动子区（BCP）及前C区的序列变异情况,并对这些变异可能造成的病毒抗原表达,疫苗逃逸,患者病症改变等情况进行探讨。最终成功扩增82例HBV全长基因序列,其中B基因型56例,C基因型26例。基因组特定功能区序列分析发现慢性HBV感染者HBV基因在S区（23.2%）、BCP区（61.0%）和前C区（29.3%）均出现了不同程度的变异。其中主蛋白（HBsAg）主要抗原决定簇a决定簇45.8%位点出现了变异,这些变异位点中包括与肝炎重症化及免疫逃逸密切相关的位点（aa126、aa129、aa145等）。位点G1896A（19.5%）,G1764A（11.0%）和A1762T（9.8%）依然是BCP/前C区的主要突变位点。而位点A1752G（25.6%）高突变率的出现在BCP区应引起关注。此外位点G1764A（χ2=5.742,P=0.030）、A1896G（χ2=14.392,P=0.000）以及A1762T/G1764A（χ2=7.289,P=0.012）的突变更容易发生在HBeAg阴性的样品中;而位点A1846T（χ2=11.882,P=0.003）、A1762T（χ2=6.561,P=0.038）和A1896G（χ2=6.958,P=0.030）的突变与HBV-DNA的病毒载量存在一定相关性。总之,福建省慢性HBV感染者在HBV不同基因功能区域均存在不同程度的变异,一些与HBeAg表达情况、HBV-DNA载量、疫苗免疫逃避及肝细胞癌发生具有相关联的变异位点已经出现,BCP区A1752G位点的高频率出现应值得关注,对于这些变异位点的患者应加强监测。To investigate the molecular characteristics of the hepatitis B virus（HBV）genome in chronic HBV infection in Fujian Province of China,serum samples were collected from patients with chronic HBV infection.HBV DNA was extracted for amplification of surface genes,basic core promoter（BCP）genes and precore（Pre-C）genes amplification.Polymerase chain reaction（PCR）products were sequenced and compared with standard sequences in GenBank.Sequencher,MEGA5 and Bioedit were used for mutation analyses of the HBV genome.We obtained 82 complete sequences of HBV.In all sequences,56 were B genotype and 26 were C genotype.Gene sequencing revealed that these HBV gene sequences in S（23.2%）,BCP（61.0%）and Pre-C（29.3%）regions had a different degree of variation.The frequency of a determinant amino acid（aa）variant was 45.8%.Those mutation sites might be correlated with severe liver diseases and immune escape,such as the sites of aa126,aa129 and aa145.Analyses revealed that site G1896 A（19.5%）,G1764 A（11.0%）and A1762 T（9.8%）remained the major mutations in the BCP/PreC region.Simultaneously,the high mutation rate of A1752 G（25.6%）in BCP merited attention.G1764 A（χ2=6.498,P=0.013）,A1896 G（10.444,0.001）and A1762 T/G1764 A）mutations were more likely to occur in HBeAg-negative samples.A1846 T（χ2=11.882,P =0.003））,A1762 T（6.561,0.038）and A1896 G（6.958,0.030）mutations had some relevance with HBV DNA load.In conclusion,People with chronic HBV infection in Fujian Province had different degrees of variation in HBV gene-function areas.Some of these mutations were associated with HBeAg expression,HBV DNA load,immune evasion of vaccines,and occurrence of hepatocellular carcinoma.Patients with these mutations need strengthened monitoring.

关 键 词：乙型肝炎病毒(HBV) 基因变异 基本核心启动子(BCP) 前C区 

分 类 号：R373.2[医药卫生—病原生物学]