Institute of Biotechnology and Genetic Engineering, KP University ofAgriculture, Peshawar, Pakistan.
Virol J. 2011 May 25;8:258. doi: 10.1186/1743-422X-8-258.
Hepatitis C virus (HCV) genotype 3a is known to show comparatively better response to combination therapy than genotype 1 and 4. Mutations within NS5A gene of HCV have earlier been implicated with response to interferon (IFN) therapies in chronic HCV patients among various populations. As response to therapy are available in different populations because of the ethnic and viral factors and there was no study available on the phenomenon of resistivity to IFN.
Chronic HCV 3a infected Pakistani patients were kept on IFN-α and ribavirin therapy for six months. NS5A gene of HCV was amplified and sequenced in the case of all the patients prior to therapy and the sequences were analysed for mutations. Out of the total 27 patients, 20 (74.07%) were observed with sustained virological response (SVR), 4 (14.81%) patients were non responder (NR) while 3 (11.11%) patients exhibited in end of treatment response (ETR). Three (3/20) (15%) SVR patients and two (2/3) ETR patients had mutations (ranging from I-V amino acids) within the NS5A ISDR regions. While the rest of the SVR patients (85%) and the NR had no mutations at ISDR region when compared with HCV K3a ISDR.
Mutations within the NS5A gene of HCV 3a genotype may not influence the outcome of combination therapy in Pakistani populations.
丙型肝炎病毒（HCV）基因型 3a 与基因型 1 和 4 相比，联合治疗的反应较好。在不同人群的慢性 HCV 患者中，HCV 的 NS5A 基因内的突变与对干扰素（IFN）治疗的反应有关。由于种族和病毒因素，不同人群的治疗反应不同，而且目前还没有关于 IFN 耐药性现象的研究。
慢性 HCV 3a 感染的巴基斯坦患者接受 IFN-α和利巴韦林治疗六个月。在治疗前对所有患者的 HCV NS5A 基因进行扩增和测序，并对序列进行突变分析。在总共 27 名患者中，20 名（74.07%）观察到持续病毒学应答（SVR），4 名（14.81%）患者无应答（NR），3 名（11.11%）患者在治疗结束时应答（ETR）。3 名（3/20）（15%）SVR 患者和 2 名（2/3）ETR 患者在 NS5A ISDR 区域有突变（范围从 I-V 氨基酸）。而其余的 SVR 患者（85%）和 NR 与 HCV K3a ISDR 相比，在 ISDR 区域没有突变。
HCV 3a 基因型 NS5A 基因内的突变可能不会影响巴基斯坦人群联合治疗的结果。
