用RFLP和PCR—RFLP技术研究东北虎和华南虎线粒体DNA多态性

采用ｍｔＤＮＡＲＦＬＰ和ＰＣＲＲＦＬＰ技术研究了东北虎和华南虎的ｍｔＤＮＡ的多态性。在ｍｔＤＮＡＲＦＬＰ研究中，分离纯化了东北虎和华南虎肝、肾和心脏组织的ｍｔＤＮＡ，用２０种识别６碱基对的限制性内切酶消化，结果只有１种限制性内切酶（ＸｂａⅠ）检测到多态性片段，其余１９种限制性内切酶消化产生的限制性格局在东北虎和华南虎完全一致。在ＰＣＲＲＦＬＰ研究中，用ＰＣＲ技术分别扩增了东北虎和华南虎ｍｔＤＮＡ的控制区（ｃｏｎｔｒｏｌｒｅｇｉｏｎ），用８种识别４碱基对的限制性内切酶分别对扩增产物进行消化，结果只有１种限制性内切酶（ＲｓａⅠ）检测到多态性片段。ｍｔＤＮＡＲＦＬＰ及ＰＣＲＲＦＬＰ的结果均提示东北虎和华南虎之间的遗传距离极小。这可能与下列因素有关：两者分布区间无天然隔离屏障；具有强扩散能力；近几百年才被相互隔离。

Molecular foundation and clinical significance of Hepatitis C virus genomic variability

Hepatitis C virus (HCV) is an enveloped virus with a plus stranded RNA genome.It contains a large open reading frame (ORF) encoding a polyprotein which can be proteolytically cleaved to structural and nonstructural proteins with different functions.The isolates of HCV show substantial nucleotide sequence variability distributed throughout the viral genome.HCV isolates can be classified into many genotypes and subtypes.Studies on HCV heterogeneity has an important guiding significance for the pathogenesis,epidemiology,diagnose and therapy of HCV.