Christdas J, Sivakumar J, David J, Daniel H D J, Raghuraman S, Abraham P
Department of Clinical Virology, Christian Medical College, Vellore, Tamil Nadu, India.
Indian J Med Microbiol. 2013 Oct-Dec;31(4):349-53. doi: 10.4103/0255-0857.118875.
Hepatitis C virus (HCV) is a leading cause of chronic liver disease (CLD) that can progress to cirrhosis and hepatocellular carcinoma. Genotypes of HCV can vary in pathogenicity and can impact on treatment outcome.
To study the different genotypes among patients with HCV related CLD attending a tertiary care hospital in south India during 2002-2012.
Study subjects were those referred to clinical virology from the liver clinic. Genotyping was performed using the genotype specific core primers in nested polymerase chain reaction (PCR), 5' non-coding regions based PCR- restriction fragment length polymorphism and NS5B sequencing methods. With the latter method, obtained sequences were compared with published GenBank sequences to determine the genotype.
Of the 451 samples tested, HCV genotype 3 was found to be the most predominant (63.85%). Other genotypes detected were genotype 1 (25.72%), genotype 2 (0.002%), genotype 4 (7.5%) and genotype 6 (2.7%). Genotype 3 was the common genotype in patients from Eastern India while genotype 1 and 4 were mainly seen in South Indian patients. Genotype 6 was seen exclusively in patients from North-Eastern India. Two other patients were infected with recombinants of genotype 1 and 2.
In this study spanning a decade, HCV genotype 3 and genotype 1 were found to be the predominant genotypes in the Indian sub-continent. Genotype 4 and genotype 6 appeared to show some geographic restriction. A continued monitoring of HCV genotypes is essential for the optimum management of these chronically infected patients. In addition, knowledge of circulating genotypes could impact on future vaccine formulations.
丙型肝炎病毒（HCV）是慢性肝病（CLD）的主要病因，可进展为肝硬化和肝细胞癌。HCV的基因型在致病性方面可能有所不同，并会影响治疗结果。
研究2002年至2012年期间在印度南部一家三级护理医院就诊的HCV相关CLD患者中的不同基因型。
研究对象是从肝脏诊所转诊至临床病毒学科室的患者。使用巢式聚合酶链反应（PCR）中的基因型特异性核心引物、基于5'非编码区的PCR-限制性片段长度多态性以及NS5B测序方法进行基因分型。使用后一种方法时，将获得的序列与已发表的GenBank序列进行比较以确定基因型。
在检测的451个样本中，发现HCV基因型3最为常见（63.85%）。检测到的其他基因型为基因型1（25.72%）、基因型2（0.002%）、基因型4（7.5%）和基因型6（2.7%）。基因型3是印度东部患者中的常见基因型，而基因型1和4主要见于印度南部患者。基因型6仅在印度东北部患者中出现。另外两名患者感染了基因型1和2的重组体。
在这项为期十年的研究中，发现HCV基因型3和基因型1是印度次大陆的主要基因型。基因型4和基因型6似乎表现出一定的地理局限性。持续监测HCV基因型对于这些慢性感染患者的最佳管理至关重要。此外，了解流行的基因型可能会影响未来的疫苗配方。
