肝癌高发区广西隆安县乙型肝炎病毒株全基因序列分析

目的 探讨肝癌高发区广西隆安县乙型肝炎病毒(HBV)株的全基因序列是否存在地域特殊性。方法 用套式PCR(nPCR)扩增该县HBV无症状携带者血清HBV全基因，用克隆测序法测序并做同源性对比。结果 本病毒株共3215个碱基，基因型为C，血清型为adw。其P基因区有40处发生碱基点突变，导致11个氨基酸改变；S基因区的前S1、前S2和S基因分别有11、2和3个碱基点突变，分别导致3、1、1氨基酸改变，未发现“a”区突变；X基因区共有6个碱基点突变，导致4个氨基酸改变，其中出现能影响e抗原表达的双突变(nt1762A→T、1764G→A)；未发现前C区基因突变，C基因有13个碱基发生突变，导致2个氨基酸改变。本病毒株与越南北部病毒株高于同为C基因型的上海株、北京株、西藏株。结论 未发现肝癌高发区的本例HBV基因C型的隆安株，基因虽有肝癌高发性，但无地域特殊性。

Full-length sequence of hepatitis B virus isolated from high incidence hepatocellular carcinoma area-Longan county

OBJECTIVE: To understand full-length sequence of HBV isolated from high incidence hepatocellular carcinoma area-Longan county, Guangxi. METHODS: The nested polymerase chain reaction (nPCR) was used for amplifying the whole HBV DNA in sera of asymptomatic carriers. The products were sequenced by clone sequencing and homological analysis. RESULTS: This isolate contained 3 215 bases. The genotype was C and the serotype was adw. There were 40 point mutations in polymerase gene which made 11 amino acids change. There were 11,2 and 3 point mutations in PreS1, PreS2 and S gene respectively which made 3,1,1, amino acids change. Six point mutations including the double mutations (nt 1762 A to T, 1764 G to A) were found in X gene leading to 4 amino acids change. There were 13 point mutations in C gene which made 2 amino acids change. No mutation was found in a determinant and Pre C. The isolate was quite close to the isolate from Vietnamese in evolution while far from the genotype C isolates from Shanghai, Beijing and Tibet. CONCLUSION: No special sequence was found in the isolate from high incidence hepatocellular carcinoma area, Longan county, Guangxi.