云南西双版纳地区乙型肝炎病毒基因型和基因亚型研究

Hepatitis B virus genotypes and subgenotypes in Xishuangbanna, China

目的探讨云南西双版纳地区乙型肝炎病毒(HBV)基因型和基因亚型分布情况。方法选取2012年5月至2013年4月西双版纳地区汉族和人数最多的两个少数民族(傣族和哈尼族)人群为研究对象,采用巢式PCR、基因序列测定等技术获取HBV全基因组序列后,构建系统进化树并计算遗传距离鉴定HBV基因型和基因亚型。结果在此地区人群中共检出3种HBV基因型:B基因型139例(76.0%),其中以B2亚型为主(105例,57.4%),quasi B3亚型次之(34例,18.6%);C基因型41例(22.4%),主要为C1亚型(33例,18.0%),其次为C2(4例,2.2%)和C5(4例,2.2%)亚型;I基因型3例(1.6%)。三民族人群HBV基因型与基因亚型分布比较:哈尼族人群HBV基因型分布与其他两个民族显著不同(哈尼族vs汉族:χ2=8.416,P=0.006;哈尼族vs傣族:χ2=15.636,P<0.001),其B基因型显著高于其他两个民族,同时没有发现I基因型;三民族人群HBV基因亚型组成也显著不同(汉族vs傣族:χ2=33.598,P<0.001;汉族vs哈尼族:χ2=22.102,P<0.001;哈尼族vs傣族:χ2=16.129,P=0.001),quasi B3亚型仅存在于傣族和哈尼族等少数民族人群,汉族人群中未检出;傣族C1亚型较其他两个民族人群高,且C5仅在傣族人群中发现;哈尼族人群C基因亚型全部为C1亚型。结论此地区HBV基因型和基因亚型分布复杂且不同民族人群HBV基因型和基因亚型分布具有民族的自身特点。

Objective To investigate the distribution of hepatitis B virus(HBV)genotypes and subgenotypes in Xishuangbanna,Yunnan Province,China.Methods Study subjects were selected from people of Han nationality and two ethnic minorities(Dai and Hani)from May2012to April2013,which are the two largest ethnic groups in Xishuangbanna.Nest-PCR and gene sequencing were performed to obtain the full genome sequence of HBV,and HBV genotypes and subgenotypes were analyzed by phylogenetic tree construction and genetic distance calculation.Results Tree analysis of the full genome sequence of HBV detected three HBV genotypes in this areas:139(76.0%)cases of genotype B,among which105(57.4%)were subgenotype B2and34(18.6%)were subgenotype quasi B3;41(22.4%)cases of genotype C,among which33(18.0%)were subgenotype C1(18.0%),4(2.2%)were subgenotype C2,and4(2.2%)were subgenotype C5(2.2%);and3(1.6%)cases of genotype I.Comparative analysis of HBV genotype and subgenotype distribution in the three populations revealed that the HBV genotype distribution in Hani people was significantly different from that in other two ethnic groups(Hani vs Han:χ2=8.416,P=0.006;Hani vs Dai:χ2=15.636,P<0.001);the prevalence of genotype B was significantly higher in Hani people than in the other two groups,but genotype I was not detected in Hani people.The distribution of HBV subgenotypes in the three populations was significantly different as well(Han vs Dai:χ2=33.598,P<0.001;Han vs Hani:χ2=22.102,P<0.001;Hani vs Dai:χ2=16.129,P=0.001).Subgenotype quasi B3existed only in Dai and Hani minority populations but not in Han nationality.The prevalence of subgenotype C1in Dai people was higher than that in the other two ethnic groups,and subgenotype C5was detected only in Dai people.The subgenotypes of genotype C in Hani population were all subgenotype C1.Conclusion The distribution of HBV genotypes and subgenotypes in this area is complicated and has unique characteristics among different ethnic groups.