目的：探讨非甲－非庚型急慢性病毒性肝炎患者肝组织中ＴＴＶ（ｔｒａｎｓｆｕｓｉｏｎ－ｔｒａｎｓｍｉｔｅｄｖｉｒｕｓ，ＴＴＶ）ＤＮＡ表达与临床病理的关系。方法：采用地高辛素标记ＴＴＶＤＮＡ探针以原位杂交技术对１９例血清学病毒标记非甲～非戊型、免疫组化检测肝组织中ＨＧＶＮＳ５阴性的病毒性肝炎患者石蜡包埋肝组织进行了检测，并对其中７例相应血清进行了ＰＣＲ检测。结果：急慢性病毒性肝炎肝组织中ＴＴＶ基因的总检出率为３１５８％，其中急性轻型肝炎的检出率为３０８％（４／１３），慢性肝炎３３３３％（２／６）。ＴＴＶＤＮＡ表达于肝细胞核或胞浆内，以核型多见。在急性肝炎，ＴＴＶ阳性细胞弥漫分布于肝小叶内，慢性肝炎于汇管区附近较为密集。阳性病例除１例慢性肝炎外，均有转氨酶的升高，肝组织与血清中的ＴＴＶＤＮＡ检出结果大致相同。结论：在不明原因病毒性肝炎患者肝组织中ＴＴＶＤＮＡ的检出表明ＴＴＶ为一种新型的肝炎病毒，ＴＴＶ为一种嗜肝性病毒，并能引起临床和病理改变 Objective: To investigate the relationship between TTV (TTV) DNA expression and clinical pathology in non-A-non-G-type acute and chronic viral hepatitis. Methods: Totally 19 cases of serological virus were labeled with non-A to non-E type using digoxigenin-labeled TTVDNA probe by in situ hybridization. Paraffin-embedded liver tissues of patients with viral hepatitis with negative HGVNS5 in liver tissue were detected by immunohistochemistry The detection and 7 cases of corresponding serum PCR test. Results: The overall detection rate of TTV gene was 3158% in acute and chronic viral hepatitis. The detection rate of acute hepatitis was 308% (4/13), chronic hepatitis 3333% (2 / 6). TTVDNA expression in the nucleus or cytoplasm of liver cells, karyotype more common. In acute hepatitis, TTV positive cells are diffusely distributed in the hepatic lobules and chronic hepatitis is more dense in the vicinity of the portal area. Positive cases in addition to a case of chronic hepatitis, have elevated transaminases, liver tissue and serum TTVDNA detection results are about the same. Conclusions: The detection of TTVDNA in liver tissue of patients with unexplained viral hepatitis shows that TTV is a new type of hepatitis virus, TTV is a hepadnavirus and causes clinical and pathological changes