宁波市麻疹病毒血凝素基因的序列分析

目的：探讨现阶段在宁波市流行的麻疹野病毒的基因型别和特征。方法：在2004年和2005年医院住院麻疹病人中采集含漱液分离麻疹病毒，获得8株麻疹野病毒。通过RT-PCR方法扩增其中两株麻疹病毒血凝素（H）基凼全序列并对其进行序列测定和分析。比较这两株麻疹病毒和Genbank中麻疹病毒的各基因型代表株的同源性。结果：两株宁波麻疹毒株ningbo04-2和ningbo05-2的H基因之间核苷酸同源性为97．7％，与川基因型代表株China93-7之间核苷酸同源性分别为98．3％，97．7％。与它们在核苷酸水平上同源性最高的毒株分别是zhejiang05-2，china94-7，其同源性分别达到99，7％，99．4％。ningbo04-2在氨基酸240位由丝氨酸（S）突变成天冬酰胺（N），造成一个潜在的N型糖基化位点丢失。结论：宁波市麻疹流行株属于H1型，至少存在H1a，HIb两组。

Sequence analysis of the hemagglutinin gene of measles virus isolated in Ningbo city, China

Objective:To investigate the genetic characterizations and genotypes of measles viruses currently prevalent in Ningbo city.Methods:Eight wild measles virus strains were isolated from the nasopharyngeal aspirates of the measles patients admitted in hospitals in Ningbo during the year of 2004 to 2005.The complete hemagglutinin(H) genes were amplified by RT-PCR and sequence analysis was conducted from 2 of the 8 virus strains.Results:H genes homogeneity of the two strains ningbo04-2 and ningbo05-2 was 97.7%.And the homogeneities of H gene were 98.3% and 97.7% respectively while compared to the representative H1genotype strain China93-7.Among the published measles strains,the highest degrees of H gene homogeneity with ningbo04-2 and ningbo05-2 were found in zhejiang05-2 and china94-7 strains,with the homogeneity as high as 99.7% and 99.4% respectively.In the strain ningbo04-2,a replacement of serine residue by asparagines at the amino acid location 240,which resulted in the loss of a latent N-linked glycosylation site.Conclusion:The measles viruses prevalent in Ningbo belong to genotype H1.Two subgroups,H1a and H1b may exist.