Luo K X, Yang J, Li X H
Nanfang Hospital, Guangzhou.
Zhonghua Yi Xue Za Zhi. 1994 Aug;74(8):478-80, 518.
We designed a mispairing primer, which could introduce a Bsu36I restriction site into the amplified fragment of A83 mutant. Following PCR, the 102bp was diagnosed by the restriction endonuclease, and the variation was detected by demonstration of 82bp and 20bp bands on gel electrophoresis (RFLP). With the method, 77 cases of acute and chronic HBV infections were analysed. Among those, 31 (65%) mutants were detected in 48 anti-HBe-positive cases, and in 29 HBeAg-positive cases, 11 (38%) were co-infected with mutated and wild isolates. No pre C defect was found in acute hepatitis B and chronic asymptomatic carriers, suggesting that mutation occurs only after immune selection. The HBeAg defective variant appears to be involved in the loss of virus tolerance, and therefore in the pathogenesis of acute exacerbation of chronic carriage as demonstrated in this study. The various chronic liver diseases had an approximate mutation frequency, and it seems that A83 mutation nearly makes HBV infection persist.
我们设计了一种错配引物，它可以将Bsu36I限制性酶切位点引入A83突变体的扩增片段中。PCR之后，用限制性内切酶对102bp片段进行诊断，并通过凝胶电泳（RFLP）上82bp和20bp条带的显示来检测变异。用该方法分析了77例急慢性HBV感染病例。其中，在48例抗-HBe阳性病例中检测到31例（65%）突变体，在29例HBeAg阳性病例中，11例（38%）同时感染了突变株和野生株。在急性乙型肝炎和慢性无症状携带者中未发现前C区缺陷，提示突变仅在免疫选择后发生。如本研究所示，HBeAg缺陷变异体似乎与病毒耐受性丧失有关，因此与慢性携带急性加重的发病机制有关。各种慢性肝病的突变频率相近，似乎A83突变几乎使HBV感染持续存在。
