错配PCR限制片段长度多态性分析：检测HBV前C区A＿（83）点突变

Mp-PCR-RFLP Analysis in Detection of A83 mutation in HBV PreC Region

为建立一种简易的检测ＨＢＶ前Ｃ区Ａ８３点突变的方法，设计了一种针对Ａ８３变异株的错配引物，通过ＰＣＲ，可在Ａ８３变异株的扩增产物中引入一个ＢＳＵ３６Ｉ限制酶位点，将扩增产物（１０２ｂｐ）用该酶消化，含变异者显示８２ｂｐ的酶切片段，以此判定的变异与测序结果一致。用本法检测了慢性乙型肝炎１２例和随访ＨＢｅ血清转换者５例，结果表明前Ｃ区Ａ８３变异与病变发展一致。

83 point mutation at HBV preC region makes HBeAg disappear, while virus replication and histologi-cal activity persist. This mutant is quite common in HBV infection.To develop a simpler test, we designeda mispairing primer ,which could inirect a Bsu 361 restriction site into the amplified product of A83 mutantFollowing PCR , the amplified fragment(102bp)was digested by the restriction endonuclease Bsu361 ,andthe A83 mutation was detected by demonstration of a 82bp band on gel electrophoresis(retriction fragmentlength polymorphism, RELP). The results were comfirmed by direct sequencing. With the method, 12cases of chronic hepatitis B and five similar cases followed up during HBe seroconversion were investigat-ed. The results suggested a close correlation between A83 mutation and histological activity.