title: [Study on the genetic difference of SEO type Hantaviruses].
abstract: OBJECTIVE
  To understand the genetic type of Hantaviruses and the difference between them caused by rodents in Beijing and to furhter explore the source of the infectious factors.
  
  
  METHODS
  Hantavirus RNA, isolated from lungs of rodents captured in Beijing and positive with Hantavirus antigens with frozen sectioning and Immunofluorescent assay, were reverse-transcribed and amplified with PCR with Hantavirus-specific primers.
  
  
  RESULTS
  Five of the PCR amplifications were discovered and sequenced with 300 bp sequence data of M segments (from 2003 - 2302nt according cDNA of seoul 8039 strain). Nucleotide sequence homology showed that they were sequences of SEO-type Hantavirus. Compared with SEO type Hantavirus, the nucleotide sequence homology of these samples was more than 94% while the homology of amonia acid sequence was more than 98%. When compared with HNT type Hantavirus, the homology of nucleotide sequence became less than 72% with the homology of amonia acid sequence less than 81%. Similar to other Hantavirus of SEO type, their nucleotide sequences and deduced amino acid sequences were highly preserved. Phylogenetic tree analysis showed that the five viruses could be divided into at least 4 branches.
  
  
  CONCLUSIONS
  It was quite likely that there were at least two sub-type SEO viruses with 4 branches that were circulating in Beijing.
authors.affiliation: Beijing Municipal Hygienic and Anti-epidemic Center, Beijing 100013, China.
authors.forename: X
authors.initials: X
authors.lastname: Zhang
authors.forename: S
authors.initials: S
authors.lastname: Zhou
authors.forename: H
authors.initials: H
authors.lastname: Wang
authors.forename: J
authors.initials: J
authors.lastname: Hu
authors.forename: Z
authors.initials: Z
authors.lastname: Guan
authors.forename: H
authors.initials: H
authors.lastname: Liu
mesh_terms: D004279:DNA, Viral / Q000737:chemistry; D005455:Fluorescent Antibody Technique; D005838:Genotype; D018063:Hantaan virus / Q000145:classification* / Q000235:genetics; D006801:Humans; D010802:Phylogeny; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017385:Sequence Homology
chemical_list: D004279:DNA, Viral