The distribution of hepatitis C virus genotype 1a in Yanbian area

目的 初步探讨东北部延边地区HCV基因型分布和1a型的感染状况.方法 对44例来自延边地区的HCV RNA阳性样本进行HCV5'非编码区(5'NCR)复合酶切分型分析.将分型结果为1a型的4例样品(分别为Y2、Y4、Y6、Y8)进行5'NCR和NS5B区的扩增,测序,然后与27个HCV全基因参考序列(均来自GenBank)比对并构建遗传进化树.结果 44例样品中1a/1b混合型19例(43.1%),1b型12例(27.3%),2a/1b混合型8例(18.2%),1a型4例(9.1%),2a型1例(2.3%),2b型以及3～6型未检出.其中,1a型的4例样品Y2、Y4、Y6、Y8分别与各基因型的全基因参考序列相比较,在5'NCR与1a型参考序列HC-J1的同源性最高,分别为0.990、0.990、0.990、0.990,进化树分析也证实为1a型;在NSSB区与1b型参考序列HC-J4的同源性最高,分别为0.936、0.957、0.936、0.936,进化树分析表明为1b型.结论 延边地区以1a/1b型混合感染为主,1b型和1b/2a型感染次之,与中国其他地区存在明显差异.对4例1a型HCV病毒株的分析发现,存在HCV5'NCR与NS5B分型结果不一致现象.分析推测可能是HCV基因组在生物进化过程中自然重组的表现,但尚需进一步研究证实.To investigate the distribution of Hepatitis C Virus (HCV)genotype 1a in Yanbian area, Jilin province.The genotypes of the serum specimens of 47 patients with HCV from Yanbian area were determined by Scheme ABC of RFLP based on HCV 5' noncoding region (5'NCR). The samples of type 1a (Y2, Y4, Y6, and Y8) were amplified from the 5'NCR and NS5B regions by RT-PCR, and then sequenced directly. These sequences were subjected to phylogenetic analysis with 27 reference sequences of HCV complete genomes from GenBank.44 specimens were HCV RNA positive, among which 19 specimens (43.2%) were of the type 1a/1b, 12 (27.3%) were of the type 1b, 8 (18.2%) were of the type 2a/1b, 4 (9.1%) were of the type 1a, and 1 (2.3%) was of the type 2a, however, the genotypes 2b and 3 approximately 6 lacked. The phylogenetic analysis for 1a samples showed that according to 5'NCR they belonged to type 1a, while on NS5B belonging to type 1b. The most nucleotide identity of 5'NCR was respectively 0.990, 0.990, 0.990, and 0.990 between Y2, Y4, Y6, Y8 and the isolate HC-J1 (genotype 1a), while that of NS5B was respectively 0.936, 0.957, 0.936, and 0.936 between Y2, Y4, Y6, Y8 and the isolate HC-J4 (genotype 1b).In Yanbian area the distribution of HCV genotype is different from those in other areas and 1a/1b has even replaced 1b as the most HCV genotype here. The results of genotyping 1a on 5'NCR and NS5B are completely inconsistent. This phenomenon may be the consequence of recombination in evolution.国家科技攻关项目PubMed中文核心期刊要目总览(PKU)中国科技核心期刊(ISTIC)中国科学引文数据库(CSCD)0201407-14108