中国人类嗜T细胞病毒Ⅰ型汕头株前病毒核苷酸序列分析

Nucleotide sequence analysis of provirus gene of human T-lymphotropic virus type Ⅰfrom an inhabitant of Shantou region in Southeast China

目的 了解中国人类嗜T细胞病毒Ⅰ型 (HTLV Ⅰ )的基因特点 ,寻找其传播及流行的原因 ,为进行HTLV Ⅰ诊断试剂及疫苗的研制等提供基础资料。方法 设计 2 2条引物 ,用PCR扩增出中国HTLV I汕头株 (命名为HTLV ⅠWHP)的前病毒基因进行测序、分析。结果 获得HTLV ⅠWHP前病毒的核苷酸全序列 ,共 90 3 4bp。将HTLV ⅠWHP与HTLV Ⅰ的原型ATK进行比较 ,其LTR、gag、pol、env、tax、rex区的核苷酸变异率分别为 :2 .4 %、1 .2 %、1 .1 %、2 .0 %、0 .1 9%、0 .79%。进化树的分析结果表明 ,HTLV ⅠWHP与来自日本、加勒比海、台湾以及金门岛的部分毒株最接近 ,同属于世界群a亚型。结论 HTLV ⅠWHP基因结构保守 ,来自于亚洲东北部沿海地区的HTLV Ⅰ毒株可能具有共同的起源。

Objective To characterize HTLV Ⅰgenome in China and to trace the origin of HTLV Ⅰdetected in the Chinese population. Methods High molecular weight DNA was extracted from whole blood sample of a HTLV Ⅰcarrier designated WHP, who was an inhabitant of Shantou region. PCR was carried out to amplify LTR, gag, pol, env, pX genes from genomic DNA sample using 22 different primers. PCR products were then purified and sequenced. Results The complete nucleotide sequence of HTLV Ⅰ WHP provirus(9 034bp) were obtained after fitting the overlapping DNA fragments together. The genetic composition was similar to that of prototype HTLV Ⅰ ATK , the nucleotide sequence diversities in LTR, gag, pol, env, tax, rex regions between WHP and ATK were 2.4%, 1.2%, 1.1%, 2.0%, 0.19%, 0.79%, respectively. Conclusion Phylogenetictrees constructed by the neighbor joining method showed that WHP was most closly related to HTLV Ⅰisolates from Japan, Taiwan and Kinmen and to all others that belong to a subgroup of Cosmopolitan group. These data provide insight into the origination and dissemination of HTLV Ⅰin Northeast Asia.