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目的 研究人巨细胞病毒 (humancytomegalovirus ,HCMV)UL138～UL14 2基因在临床低传代分离株中的多态性及其与HCMV先天感染致病性之间的关系。方法 对经荧光定量PCR方法检测HCMV DNA为阳性的临床分离株进行UL138～UL14 2基因全序列PCR扩增 ,对扩增阳性的标本进行全序列的测序及结果分析。结果 HCMV临床分离株的UL138、UL14 2ORF(openreadingframe)高度保守 ;UL139ORF呈现高度多态性 ,可被明确划分为 3个基因型 ,且核苷酸及氨基酸的变异主要集中在序列的 5′端 ;所有临床分离株的UL14 0ORF在Toledo株第 174位核苷酸处插入 1个胞嘧啶核苷酸 ,其ORF较Toledo株增加了 2 31个核苷酸 ;所有临床分离株的UL14 1ORF在Toledo株第 2 2 7位核苷酸处缺失了 1个胸腺嘧啶核苷酸 ,故形成UL14 1a及UL14 1b 2个新的ORF。HCMV临床分离株的UL14 0蛋白较Toledo株新增了ScAMP磷酸化和酪蛋白激酶Ⅱ磷酸化位点 ,其它基因编码蛋白的重要功能区域相对保守。结论 HCMV临床分离株UL139ORF的 5′端呈现高度多态性 ,而且被明确地分成 3个基因型 ,故其可能在HCMV先天感染的致病性差异方面起一定作用 ;尚未发现UL138～UL14 2中某个特定基因与HCMV先天感染致病性有本质联系
Objective To study the polymorphism of human cytomegalovirus (HCMV) UL138 ~ UL14 2 gene in clinical low passage isolates and its relationship with the pathogenicity of congenital infection of HCMV. Methods The full-length sequence of UL138 ~ UL14 2 gene of clinical isolates positive for HCMV DNA by real-time fluorescence quantitative polymerase chain reaction (PCR) was amplified by PCR. The full-length sequence of the amplified samples was sequenced and the results were analyzed. Results The UL138 and UL14 2ORF (openreading frames) of HCMV clinical isolates were highly conserved. UL139ORF was highly polymorphic and could be clearly divided into three genotypes. The variations of nucleotide and amino acid were mainly located at the 5 ’end of the sequence. The UL14 ORF of all clinical isolates had a cytosine nucleotide insertion at the 174th nucleotide of the Toledo strain with an ORF of 231 nucleotides greater than that of the Toledo strain. The UL14 1 ORF of all clinical isolates was significantly higher in the Toledo strain A thymine nucleotide was deleted from the nucleotide at position 2 2 7, resulting in the formation of 2 new ORFs of UL14 1a and UL14 1b. UL14 0 protein of HCMV clinical isolates added ScAMP phosphorylation and casein kinase Ⅱ phosphorylation sites compared with Toledo strain. The other gene encodes the protein’s important functional region is relatively conservative. Conclusion The 5 ’end of HCMV clinical isolates UL139 ORF is highly polymorphic and clearly divided into 3 genotypes, so it may play a role in the pathogenicity difference of HCMV congenital infection. The UL138 ~ UL142 A particular gene is intrinsically linked to the pathogenicity of congenital HCMV infection