title: [Genetic diversity of human Parvovirus B19 VP1 unique region].
abstract: OBJECTIVE
  Human Parvovirus B19 (HPV B19) is a small (23 nm), non-enveloped DNA virus found in 1974. It has been proved that HPV B19 is associated with a variety of childhood diseases, such as erythema infectious, transient aplastic crisis, aplastic anemia, idiopathic thrombocytopenic purpura and arthropathy, etc. There have been no any effective vaccines to prevent HPV B19 infection so far. The HPV B19 genome is composed of 5.6 kb single strand DNA. This genome encodes a nonstructural protein NS1, two structural proteins VP1 and VP2. Most neutralizing linear epitopes of HPV B19 cluster in the VP1 unique and VP1-VP2 junction regions. Only proteins encoded by genes of the VP1 unique and VP1-VP2 junction regions can stimulate bodies to produce protective antibodies. Aim of the present study was to get the VP1 unique region gene of HPV B19 and to analyze the genetic diversity so as to further study its function and application.
  
  
  METHODS
  The VP1 unique region gene of HPV B19 was amplified from the serum of a child with idiopathic thrombocytopenic purpura by PCR. The purified PCR product was cloned into pGEM-T easy vector and transfected into the host strain E. coli (DH5 alpha). Positive clones were chosen and then the target gene was sequenced.
  
  
  RESULTS
  The target gene sequence of HPV B19 VP1 unique region was amplified and cloned successfully. It had 705 nucleotides. Compared with the relevant sequences published in Genbank, the sequencing results were revealed with two nucleotides changes in the HPV B19 VP1 unique region, but their coding amino acid were not changed.
  
  
  CONCLUSIONS
  It is suggested that genetic diversity exists in the VP1 unique region of HPV B19. Construction of the recombinant plasmid of HPV B19 VP1 unique region gene might benefit to further study.
authors.affiliation: Department of Pediatrics, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, China.
authors.forename: Xin-hong
authors.initials: XH
authors.lastname: Qian
authors.forename: Guo-cheng
authors.initials: GC
authors.lastname: Zhang
authors.forename: Xi-ying
authors.initials: XY
authors.lastname: Jiao
authors.forename: Ping
authors.initials: P
authors.lastname: Zhang
authors.forename: Xin
authors.initials: X
authors.lastname: Sun
authors.forename: Yu-hong
authors.initials: YH
authors.lastname: Cao
authors.forename: Dong-liang
authors.initials: DL
authors.lastname: Xu
authors.forename: Lin-lin
authors.initials: LL
authors.lastname: Fei
authors.forename: Wen-jin
authors.initials: WJ
authors.lastname: Huang
mesh_terms: D036022:Capsid Proteins / Q000235:genetics*; D002648:Child; D004279:DNA, Viral / Q000737:chemistry / Q000235:genetics; D014644:Genetic Variation; D006801:Humans; D009154:Mutation; D016732:Parvovirus B19, Human / Q000235:genetics*; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA
chemical_list: D036022:Capsid Proteins; D004279:DNA, Viral; C095547:capsid protein VP1, parvovirus B19