通过ＲＴＰＣＲ技术扩增了甲肝病毒减毒株（Ｈ２）全长ＲＮＡ，并对长片段ＲＴＰＣＲ扩增进行了方法学上的探讨．采用抗血清特异沉淀病毒；盐酸胍酸性酚、氯仿一步法分离纯化病毒ＲＮＡ，可得到高质量的ＲＮＡ样品；以此ＲＮＡ为模板，在无ＲＮＡ酶的逆转录酶作用下，合成单链ｃＤＮＡ；继续以此ｃＤＮＡ为模板，利用３２ｍｅｒ寡核苷酸引物，在Ｔａｑ和ＤｅｅｐＶｅｎｔＤＮＡ多聚酶的作用下进行ＰＣＲ扩增，得到７４ｋｂ的扩增产物 The full-length RNA of attenuated strain of hepatitis A virus (H2) was amplified by RT-PCR and the method of RT-PCR amplification of long fragments was studied. High-quality RNA samples can be obtained by using antiserum-specific precipitated virus, guanidine hydrochloride-acidic phenol and chloroform one-step isolation and purification of viral RNA. Using this RNA as a template, single-stranded cDNA was synthesized under the action of RNase-free reverse transcriptase ; Continue to use the cDNA as a template, the use of 32mer oligonucleotide primers, Taq and DeepVentDNA polymerase under the action of PCR amplification to give 7  4kb amplification products