Blum H E
Department of Internal Medicine II, University of Freiburg, Germany.
Int J Clin Lab Res. 1997;27(4):213-24. doi: 10.1007/BF02912461.
Variants of hepatitis B, C, and delta virus have been identified in patients both with acute and chronic infections. In the hepatitis B virus genome, naturally occurring mutations have been found in all viral genes, most notably in the genes coding for the structural envelope and nucleocapsid proteins. In the hepatitis C virus genome, the regions coding for the structural envelope proteins E1 and E2, as well as the 3'-contiguous non-structural region NS1, were found to be hypervariable. Viral variants may be associated with a specific clinical course of the infection, e.g., acute, fulminant or chronic hepatitis. Specific mutations may reduce viral clearance by immune mechanisms ('vaccine escape' and 'immune escape'), response to antiviral therapy ('therapy escape'), as well as detection ('diagnosis escape'). The exact contribution, however, of specific mutations to the pathogenesis and natural course of hepatitis B, C, or delta virus infection, including hepatocellular carcinoma development, and the response to antiviral treatment remains to be established.
在急性和慢性感染患者中均已鉴定出乙型、丙型和丁型肝炎病毒的变体。在乙型肝炎病毒基因组中，所有病毒基因均发现了自然发生的突变，最显著的是编码结构包膜和核衣壳蛋白的基因。在丙型肝炎病毒基因组中，编码结构包膜蛋白E1和E2的区域以及3' 相邻的非结构区域NS1被发现具有高度变异性。病毒变体可能与感染的特定临床病程有关，例如急性、暴发性或慢性肝炎。特定突变可能会通过免疫机制降低病毒清除率（“疫苗逃逸”和“免疫逃逸”）、对抗病毒治疗的反应（“治疗逃逸”）以及检测（“诊断逃逸”）。然而，特定突变对乙型、丙型或丁型肝炎病毒感染的发病机制和自然病程（包括肝细胞癌的发生）以及对抗病毒治疗的反应的确切作用仍有待确定。
