Genetic characterization of rubella virus isolated in Guizhou Province from 2012 to 2015
10.3760/cma.j.issn.0253-9624.2017.12.011
- VernacularTitle: 贵州2012—2015年风疹病毒分离株基因特征分析
- Author:
Xiaomin TANG
1
;
Zhen ZHU
;
Gang REN
;
Xufang YE
;
Li ZHANG
Author Information
1. Department of Immunization Programs, Guizhou Provincial Center for Disease Control and Prevention, Guiyang 550004, China
- Publication Type:Journal Article
- Keywords:
Rubella virus;
Genotype;
Sequence analysis
- From:
Chinese Journal of Preventive Medicine
2017;51(12):1108-1112
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To analyze the genetic characteristics of rubella virus isolated from 2012 to 2015 in Guizhou province.
Methods:A total of 390 cases of suspected measles were collected from Guizhou measles network laboratory from 2012 to 2015 and 25 cases of rubella cases were diagnosed. Rubella virus isolation was performed using Vero/SLAM cells. The presence of rubella viral RNA was detected using Real-time RT-PCR after RNA extraction from infected tissue culture cells. Fragments of 480 bp and 633 bp nucleotides of E1 genes of the isolates were amplified by RT-PCR and the PCR products were sequenced and spliced. The phylogenetic tree was conducted based on the 739 bp nucleotide sequences of E1 genes and gene characteristic analysis was performed.
Results:There were 19 cases of rubella outbreaks and 6 cases of rubella sporadic cases in 25 cases of suspected rubella cases. There were 11 males (44.0%) and 14 females (56.0%). The mean age and standard deviation were (12.3±3.9) years. A total of 10 rubella strains were isolated. The results of phylogenetic analysis showed that 7 strains of rubella virus isolates belonged to genotype 1E and the other belonged to genotype 2B. The nucleotide acid and amino acid homology among 7 strains 1E genotype were 99.0%-100% and 100% respectively. 2B genotype of 3 strains of nucleotide and amino acid homology were 99.4%-100% and 99.5%-100% respectively. Ten strains of rubella virus were not mutated in the E1 glycoprotein gene, Asn 177 and Asn 209 N-type glycosylation sites and E1 antigen epitopes between 213 and 285aa.Among them, 7 strains of 1E genotype had a mutation from leucine to phenylalanine in 338 amino acid, 2 strains of 2B genotype at 377 amino acids from valine to alanine.
Conclusion:Rubella virus epidemic was caused by 1E and 2B genotypes in Guizhou from 2012 to 2015.Ten strains of rubella virus were highly conserved in nucleotide and amino acid sequences and there was no variation of important functional sites.