中国云南少数民族地区慢性乙型肝炎患者病毒基因型的鉴定  

Identification of hepatitis B virus genotypes in patients with chronic hepatitis B from different nationalities in ethnic minority areas in Yunnan Province, China

作　　者：边中启[1] 华占楼[1] 严维耀[2] 刘明秋[2] 吴殿源[1] 郑兆鑫[2] 

机构地区：[1]成都军区昆明总医院传染病中心,650032 [2]复旦大学遗传工程国家重点实验室

出　　处：《中华医学杂志》2006年第10期681-686,共6页National Medical Journal of China

摘　　要：目的研究乙型肝炎病毒(HBV)基因型在不同民族慢性乙型肝炎(CHB)患者中是否存在进化差异及临床意义。方法应用聚合酶链反应(PCR)对中国云南少数民族地区50例CHB患者(25例少数民族CHB患者与对照组25例汉族CHB患者)HBV前S2/S(preS2/S)和C(core,C)基因进行扩增,将PCR扩增产物克隆到载体pBS(pBluescriptⅡSK,pBS)上进行测序分析。结果50例患者HBVpreS2/S基因全长846bp,GC含量占49.1%,编码281个氨基酸(aa);C基因全长552bp,GC含量占46.1%,编码183个aa。并在GenBank登录注册(AY517619、AY517620、AY517488、AY517489、AY517598、AY517599)。通过与GenBank数据库中HBV基因及亚型序列比较,发现全部患者HBV基因与ayw1亚型具有高度同源性,preS2/S基因aa同源性为97.5%～98.6%,C基因aa同源性为94.5%～97.8%。所有患者S基因在“a”抗原决定簇aa第122位为精氨酸(AGA)、第160位为赖氨酸(AAA)。发现全部患者HBV基因型均为B型(属ayw1亚型),未发现其他基因型。HBV准种发生频率为4%。25例少数民族CHB患者之间与对照组25例汉族患者之间HBV基因型B差异比较,差异无统计学意义(P>0.05)。所有患者preS2/S基因均存在aa124精氨酸(R)→赖氨酸(K124)(1.1%)、172亮氨酸(L)→脯氨酸(P172)(1.3%)、306蛋氨酸(M)→苏氨酸(T306)(1.5%)和361异亮氨酸(I)→蛋氨酸(M361)(1.6%)的aa替代,其发生替代的频率>1%。但所有患者发生aa145甘氨酸(G)→精氨酸(R)(0.4%)替代的频率<1%。50例患者C基因在T细胞和B细胞表位存在27～63、80～110、135～153位间aa变异,其中45例患者C基因由于nt1979A→G,nt2012T→A,nt2088G→T,nt2304C→A和nt2339A→G的变异,分别引起V27、N38、V63、Q135和A147的aa替代,其发生替代的频率>1%。而另外5例重型CHB患者C基因由于nt2159A→G,nt2189A→C的变异,分别引起甘氨酸(G87)和亮氨酸(L97)的aa替代。所有患者preS2/S和C基因中未发现碱基的插入或缺失。结论中国云南少数民族地区HBV流行毒株为基因Objective To determine whether there is evolutionary difference in hepatitis B virus （HBV） genotypes among the patients with chronic hepatitis B （CHB） of different nationalities and its clinical significance. Methods Peripheral blood samples were collected from 50 CHB patients, 25 of diverse nationalities and 25 of Han nationality from the ethnic minority regions in Yunnan Province, China, The HBV preS2/S （pre S2/S） and C genes were amplified by PCR. The PCR products were inserted into the vector pBluescript Ⅱ SK （pBS）. The cloned preS2/S and C genes were sequenced. Resnlts The sequences of HBV preS2/S and C genes from the 50 patients were 846 （with 49.1% of GC） and 552 （ with 46. 1% of GC） nucleotides （nt） in length, and encoded 281 and 183 amino acids （aa） respectively. These findings were registered in GenBank Accession Numbers ： AY517619, AY517620, AY517488, AY517489, AY517598, AY517599. Compared with the HBV and subtype sequences in the GenBank database, the HBV preS2/S and C genes among all the subjects were homologous to aywl in sequence by 97.5% -98.6% and 94.5%-97.8% respectively. The ＂a＂ determinant region of S genes in all cases were found to be Arginine （AGA） and Lysine （AAA） at corresponding aa 122 th and 160 th respectively. HBV genotype B was identified in all patients with CHB （aywl subtype）. Genotypes A, C, D, E, F, G, and H were not detected in any of them. The quasi-spocies nature of the HBV in the sera was observed in 2 of the 50 samples examined （4%）. There was not a significant difference in the prevalence of HBV genotype B between the 25 diverse nationality patients and the 25 control Han nationality patients （ P 〉 0.05 ）. In the 50 CHB patients, the preS2/S genes were identified to have aa substitutions at the positions R124K （1.1%）, L172P（ 1.3% ）, M306T（ 1.5% ）, and I361M（ 1.6% ） ,with a frequency of more than 1%. In all subjects, the frequency of aa G145R （0.4%） substitutions was less than 1%. In all subjec

关 键 词：肝炎病毒 乙型 序列分析 基因型 少数民族 

分 类 号：R512.62[医药卫生—内科学] R512.6[医药卫生—临床医学]