慢性无症状乙型肝炎病毒携带者的基因型研究

目的：采用多对型特异性引物，通过巢式PCR检测慢性HBV无症状携带者中的HBV基因型分布情况。方法：根据从前S1基因到S基因中的保守序列设计出10条内外引物，并将其中8条内引物分成2组，分别扩增A，B，C和D，E，F型，根据PCR产物大小判定HBV基因型。用此方法检测北京地区HBV慢性无症状HBV携带者血清。结果：265例慢性无症状HBV携带者中，HBV DNA阳性113例，阳性率42．6％。检测到B，C基因型分别为B基因型29例（25．7％），C基因型80例（70．8％），B基因型和C基因型混合感染4例（3．5％）。不同基因型在不同性别构成比例和HBeAg阳性率的差别无统计学意义。结论：北京地区慢性无症状HBV携带者HBV DNA阳性患者中以B，C型为主，C型占优势，存在少量B和C基因型混合感染。

Detection for Genotypes of Hepatitis B Virus in Chronic Asymptomatic HBV Carriers

Objective: To determine the genotypes of hepatitis B virus (HBV) in chronic asymptomatic HBV carriers by nested PCR with multiplex pairs of genotype-specific primers. Methods: Ten outer and inner primers were designed on the basis of the conserved nature of nucleotide sequences in regions of the Pre-S1 through S genes, in which 8 inner primers were divided into 2 group including genotype A-C and genotype D-F respectively. Genotypes of HBV were determined directly by the PCR products. PCR was used in the genotyping of HBV in 265 chronic asymptomatic HBV carriers in Beijing. Results: One hundred and thirteen samples (42.6%) were HBV DNA positive in the 265 chronic asymptomatic HBV carriers. In the 113 HBV DNA positive samples, 29 samples(25.7%)were genotype B and 80 samples (70.8%)were genotype C, 4 and samples (3.5%)were both genotype B and C positive. There were no statistical difference in proportion of genotypes between male and female and HBeAg positive rate between genotype B and genotype C. Conclusion: The predominant genotypes of HBV in chronic asymptomatic HBV carriers in Beijing are genotype B and C. The major genotype is genotype C. There are few genotype B and C mixed infection.