贵州地区不同人群TTV核酸检测及部分核苷酸序列分析

目的 了解贵州地区TTV感染状况，分析TTV贵州株的基因特点。方法 以公布的TTV第1读码区序列设计两对寡核苷酸引物，用套式聚合酶链反应法(nested—PCR)检测贵州地区不同人群血清中TTV核酸(TTV DNA)，并对3份TTV DNA阳性血清的PcR产物，用直接测序法测定核苷酸序列。结果 62例正常人，37例志愿献血员，50例血液透析患者，107例静脉药瘾者及139例肝病患者血清中TTV DNA阳性率分别为6．45％(4／62)，8．1％(3／37)，26.0％(13／50)，25.23％(27／107)和16.55％(23／139)。在肝病组中，重型肝炎、肝硬化、肝癌患者的TTV DNA阳性率分别为35.71％(5／14)，14．15％(15／106)和15．79(3／19)。测定的282个核苷酸中，3株贵州株的同源性均高于99％，与日本株N22相比，同源性都为98％。结论 贵州存在TTV感染，血透患者中有较高的TTV感染率，TTV可能是重型肝炎的病原因子，3株贵州株可能为同一基因型。

Detection of TTV DNA and analysis of partial TTV gene sequence in different population of Guizhou area

Objective To investigate the prevalence of transfusion transmitted virus (TTV) infection and analyze partial nucleotide sequence of TTV isolated from Guizhou area.Methods A nested polymerase chain reaction (nPCR) assay with two set of primers deduced from the first read frame of TTV genome was established, the prevalence of TTV DNA were detected in 395 sera collecte from different population in Guizhou area. The partial genes of TTV DNA fragments amplified from two liver disease patients and one hemodialysis patient were analysed and then compared with gene from Japan strain.Rusults The positive rates of TTV DNA in 62 normal adults,37 blood donors,50 hemodialysis patients,107 intravenous drug users (IVDUs),139 patients with liver diseases were 6.45% (4/62), 8.10%(3/37), 26.00% (13/50), 25.23% (27/107) and 16.54% (23/139), respectively. The homology of TTV DNA sequence was from 99% to 100% within three Guizhou strains. As compared with published sequence, the nucleotide homology is 98% between all three Guizhou strains and Japan strain.Couclusion There are TT virus infection in Guizhou area, the infection rates were higher in hemodialysis patients and IVDUs. The nucleotide homology was high between Guizhou strain and Japan strain.