摘要目的 建立检测HBV YMDD变异的PCR产物直接测序法,并与传统实时荧光PCR检测YMDD突变的结果进行比较分析.方法 选取103份慢性乙型肝炎患者血清标本,提取血清HBVDNA.用实时荧光PCR检测YMDD突变;用巢式pcR扩增HBV逆转录酶基因,对PCR产物进行DNA双向测序,NTI软件比对结果.采用Kappa一致性检验对DNA测序法检测的rt204位点突变与实时荧光PCR检测的YMDD突变结果进行比较.结果 PCR产物直接测序法可有效检测低病毒载量标本(500拷贝/ml)和高病毒载量(1010拷贝/ml)标本,同时可以避免高病毒载量标本的抑制效应.与实时荧光PCR相比较,YIDD突变检测符合率为100%,YVDD突变检测符合率97.1%,YIDD与YVDD共生突变符合率76.2%(Kappa=0.853,P<0.01).结论 本研究建立的PCR产物直接测序法检测HBV耐药相关基因突变,灵敏度高,检测范围宽,与实时荧光PCR检测结果有较高的符合率,并可同时检出YMDD、YIDD和YVDD.

abstractsObjective To develop an assay of PCR-produet direct sequencing to detect hepatitis B virus (HBV) YMDD mutation, and compare the results gained by the sequencing and traditional real-time fluorescent PCR assays. Methods Serum samples were collected from 103 patients with chronic hepatitis B. HBV DNA were extracted from sers. YMDD mutation was detected by a commercial real-time PCR assay. Meanwhile, HBV reverse transcriptase-encoding gene was amplified by a nested PCR assay. The PCR products were directly subjected to sequencing at two directions, and the sequencing results were analyzed by NTI program. Using Kappa test, comparison was made between the results of rtM204-site mutations obtained by the direct sequencing and YMDD mutations by the real-time fluorescent PCR. Results The direct sequencing assay proved to be highly effective with bread range of detection in viral load from 500 to 1010copies/ml. And it may simultaneously avoid inhibitory effect caused by high viral load. The coincidence rates between two assays were 100% for YIDD, 97. 1% for YVDD, 76. 2% for YIDD/YVDD coexistence (Kappa = 0. 853, P < 0. 01). Conclusions The direct sequencing assay for HBV drug-resistant mutation detection is highly sensitive with broad dynamic range. It has high coincidence rate with real-time fluorescent PCR assay with advantage of detecting YMDD, YIDD and YVDD mutations simultaneously.