人巨细胞病毒UL149基因在临床低传代分离株中的多态性研究

目的研究人巨细胞病毒(humancytomegalovirus,HCMV)UL149序列在临床低传代分离株中的多态性,探讨HCMV基因多态性与其感染引起不同临床症状之间的关系。方法对29株经荧光定量PCR方法(QPCR)检测HCMVDNA为阳性的临床低传代分离株的细胞培养上清液进行HCMVUL149全序列PCR扩增,并对PCR扩增产物进行序列测定及分析。结果29株临床低传代分离株有26株PCR扩增阳性,与HCMVToledo株进行序列比较分析,26株临床分离株UL149开放阅读框架(openreadingframe,ORF)之间存在着高度的多态性,种系进化树分析结果显示26个序列可分为3个型,黄疸患儿分布以G1型为主;小头畸形以G3型为主;巨结肠仅见于G1、G2型,G3型未见。部分临床分离株存在CKP位点的缺失及TKP位点增加。结论HCMVUL149基因在临床分离株中存在着高度的多态性。来自不同临床症状分离株的UL149基因及其编码蛋白具有一定的结构特点,并与基因型呈一定的相关性。

Polymorphism of human cytomegalovirus UL149 gene in low passage clinical isolates

Objective To investigate the polymorphism of human cytomegalovirus UL149 gene in low passage clinical isolates and to identify the relationship between the polymorphism and different pathogenesis of congenital HCMV infection. Methods To amplify the entire HCMV UL149 gene region of 29 clinical isolates by PCR, which had been proven containing detectable HCMV DNA by using FQ-PCR. PCR amplification products were directly sequenced and the sequence data were analysed. Results Twenty-six of 29 isolates were amplified successfully. By comparison with Toledo sequence, the UL149 ORF in all 26 clinical isolates was classified into 3 major genotypes. There are deleted CKP sites and additional TKP sites in some clinical isolates. Conclusion HCMV UL149 sequence is hypervariable. The UL149 sequences in isolates from patients with the same symptoms showed certain structure characters, which were correspond to that of genotype. The data indicated that UL149 gene might play certain role in HCMV infection.