HBV P基因YMDD变异的检测及临床应用的初步研究

目的采用错配PCR扩增方法进行HBVP基因YMDD变异的检测，对其临床意义进行初步的研究。方法应用分子克隆方法，构建YMDD、YVDD和YIDD变异的阳性质粒，并对该方法进行敏感性及特异性试验。对65例未经抗病毒治疗的乙型肝炎患者检测YMDD变异情况。结果经PCR方法、酶切鉴定及直接测序鉴定出YMDD、YVDD和YIDD质粒构建成功，且该方法具有较好的敏感性和特异性。65例未经拉米夫定治疗的乙型肝炎患者存在YMDD变异，出现变异6例，阳性率为9．07％；其中YIDD和YI／YMDD各1例，YVDD3例，YV／YMDD1例。结论本检测方法简便、实用，在未经抗病毒治疗的患者中可存在YMDD变异，其与野生株一样是自然存在的，抗病毒药物压力不是导致HBV YMDD变异的唯一因素。

Detection of YMDD mutations in HBV polymerse gene and study of clinical practical

To detecte YMDD mutations in HBV polymerase gene by mismatch amplify mutation assay in this study and exolore clinical significance of YMDD mutations. Plasmids of YMDD, YVDD, YIDD were constructed with molecule methods. They were tested in sensitivity and specificity. YMDD mutations were analyzed in 65 patients without antivirual therapy. Plasmids of YMDD, YVDD, YIDD were identified by PCR method, restriction endonulease method and direct sequence analysis which were constructed successfully. This method was high sensitivity and specificity. YMDD mutations existed in 6 patients of 65 patients of HBV without antivirual therapy. The rate of YMDDmutations was 9.07%. There were 1 YIDD mutation strain,1 YI/YMDD mixed mutation strain, 3 YVDD mutation strains and 1 YV/YMDD mixed mutation strain in 6 patients. Conclusions] This method is simple and practical in detecting YMDD mutations of P gene of HBV.YMDD mutations are occurred in the patients of HBV without antivirual therapy. YMDD mutations exist naturally in wild type of HBV. Pressure of antivirual drug is not unique factor that leads to YMDD mutations.