扬州市乙型肝炎病毒B基因型前S基因特征分析

Genetic characterization of the Pre-S gene of hepatitis B virus with genotype B in Yangzhou

目的分析扬州市乙型肝炎病毒B基因型前S基因特征和基因突变。方法扩增HBV B基因型前S基因并测序,Clustal W比对构建距离矩阵,MegAlign比对突变位点。结果扬州6株病毒全部在HBV B基因型分支上,同源性:97.2%～98.6%,与同基因型参考株的同源性:92.8%～100%,与其他基因型参考株间的同源性为:78.1%-86.2%。前S基因与参考序列AF121244比对后发现存在缺失和突变现象,YZ07发现有4个突变位点,YZ06有3个突变位点,YZ01有1个突变位点,6例样本有3例发生突变,YZ02、03、04与参考序列比对未发现突变。结论扬州市HBV B基因型间的同源性高,流行的地域性明显,6株病毒前S基因有7个突变位点,低病毒载量毒株突变位点多于高病毒载量毒株。

Objective To study the characteristics and mutations of Pre-S gene of Hepatitis B virus in Yangzhou.Methods The Pre-s genes of Hepatitis B virus were amplified and sequenced.Clustal W alignment was used to construct the distance matrix and MegAlign was used to spot mutation sites.Results All the sequences of six viruses belonged to the gene branches of Hepatitis B virus with the nucleotide homologies of 97.2%-98.6%.The nucleotide sequences of six viruses were compared with the same genotype reference strains and other genotype reference strains,and the homologies were 92.8%-100%and 78.1%-86.2%,respectively.Compared the with the reference sequence AF21244,deletions and mutations were detected in Pre-S genes.Four mutant sites were found in YZ07,three mutant sites in YZ06,and one mutatant site in YZ01.Three of the six samples had mutations and no mutation was found in the comparison between YZ02,03 and 04 and the reference sequence.Conclusions The homologies between Hepatitis B virus genotypes in Yangzhou were high,and the endemic regional characteristics were obvious.There were seven mutant sites in six Pre-s genes,and more mutation sites in low viral load strains than high viral load strains.