Research on the genotypes of clinical varicella-zoster virus isolates in Tibet
Objective To analyze the genotypes of clinical varicella-zoster virus(VZV) isolates in Tibet.Methods The samples of vesicular fluid from patients with chickenpox or zoster were collected to isolate VZV in human embryonic fibroblast cells.Furtherly,the isolated VZV were identified by indirect immunofluorescence assay and the positive ones were continuely cultured in vitro to get their genome DNAs.Then,PCR and nucleotide sequencing were performed on the part of open reading frames 1,21,50,54.To confirm the genotypes of isolated virus strains,the gene sequences obtained from PCR products were compared with that in GenBank of VZV Dumas strains,and their restriction enzyme sites were analyzed via Primer 5.0.Results Ten clinical isolates of VZV were obtained from sixteen specimens,the positive isolation rate was 62.5％.Gene analysis showed that among all the ten clinical isolates of VZV in Tibet,three strains are genotype A1,four are genotype A2 and the other three are genotype J1.Conclusion The VZV genotype distribution in Tibet was tightly related to their special geographic locations. 
 
Key words: 
Varicella-zoster virus ;  Single nucleotide polymorphism ;  Genotype ;  Tibet area