摘要目的 了解北京市流行的风疹病毒基因型特征和变异趋势,为风疹传染病防治工作提供科学依据.方法 选取北京市风疹实验室诊断病例咽拭子标本提取病毒核酸,采用RT-PCR方法扩增风疹病毒E1基因739个核苷酸片段,对扩增产物进行核苷酸序列测定和分析.同WHO风疹病毒基因型代表株构建基因进化树,分析基因型特征、核苷酸和氨基酸的变异.结果 获得10株可用于分子流行病学研究的靶核苷酸序列.在基于WHO基因定型靶序列739个核苷酸片段构建的基因进化树上,10株风疹病毒均属于2 B基因型,相对于参考株形成一个独立分支.10株风疹病毒大部分核苷酸突变为无义突变,氨基酸序列高度保守,除了1株风疹病毒在E1蛋白血凝抑制和中和位点区域第282位氨基酸发生Ser→Phe突变,其他病毒株无重要抗原位点改变.结论 北京地区发现风疹病毒2B基因型流行株.

abstractsObjective To analyze the genotypes and the variation trend of rubella virus strains circulating in Beijing and to provide a scientific guidance for the prevention and control of rubella.Methods The viral nucleic acids were extracted from diagnostic pharyngeal swab specimens collected by Beijing rubella laboratory.The 739 nucleotides of rubella E1 gene were amplified by reverse transcription-polymerase chain reaction ( RT-PCR) .The amplified products were sequenced and analyzed.Genotypes of the rubella virus strains circulating in Beijing and variations in their nucleotides and amino acids were analyzed by comparing with those of the WHO recommended rubella virus reference strains.Results The target nucleotide se-quences of 10 rubella virus strains were obtained for molecular epidemiological study.All of the 10 strains belonged to 2B genotype and formed an independent branch according to the phylogenetic tree based on the 739 nucleotide fragments of E1 gene.Most of the nucleotide mutations occurred in the 10 strains were non-sense mutations.The amino acid sequences of the circulating strains were highly conservative.No significant mutations in the antigenic sites were identified in the rubella virus strains circulating in Beijing except that one amino acid mutation from Ser to Phe in the No.282 amino acid of E1 protein was identified in the hemag-glutination inhibition and neutralizing site of one strain.Conclusion This study indicated that the rubella virus genotype 2B epidemic strains were isolated in Beijing.