title: Genome characterization of two NADC30-like porcine reproductive and respiratory syndrome viruses in China.
abstract: BACKGROUND
  The recent emergence of NADC30-like porcine reproductive and respiratory syndrome virus (PRRSV) in vaccinated pigs arose more attentions for the high incidents of mutation and recombination of PRRSVs.
  
  
  RESULTS
  In this study, we determined full-length genome sequences of two NADC30-like PRRSV isolates from recent PRRSV outbreaks in China. Phylogenetic analysis showed that these two isolates were clustered in an independent branch together with NADC30, an American isolate in 2008. Genetically, HNjz15 shared 95.6 % nucleotide similarity to NADC30 without any exotic gene insertion. By contrast, HNyc15 shared 93.8 % similarity to NADC30 with recombination with VR-2332 and CH-1a. Two more previously reported NADC30-like PRRSVs were also analyzed and had exotic gene insertions with different PRRSV strains in their nonstructural protein genes.
  
  
  CONCLUSIONS
  The above results showed the increased mutation and recombination rates of NADC30-like PRRSV under current vaccination pressure and a more pressing situation for the PRRSV eradication and control in China.
authors.affiliation: National Research Center for Veterinary Medicine, Cuiwei Road, High-Tech District, Luoyang, 471003 Henan Province People's Republic of China.
authors.forename: Xiangdong
authors.initials: X
authors.lastname: Li
authors.affiliation: OIE Porcine Reproductive and Respiratory Syndrome Reference Laboratory, China Animal Disease Control Center, No. 20 Maizidian Road, Chaoyang District, Beijing, 100125 People's Republic of China.
authors.forename: Jiajun
authors.initials: J
authors.lastname: Wu
authors.affiliation: National Research Center for Veterinary Medicine, Cuiwei Road, High-Tech District, Luoyang, 471003 Henan Province People's Republic of China.
authors.forename: Feifei
authors.initials: F
authors.lastname: Tan
authors.affiliation: National Research Center for Veterinary Medicine, Cuiwei Road, High-Tech District, Luoyang, 471003 Henan Province People's Republic of China.
authors.forename: Yingying
authors.initials: Y
authors.lastname: Li
authors.affiliation: National Research Center for Veterinary Medicine, Cuiwei Road, High-Tech District, Luoyang, 471003 Henan Province People's Republic of China.
authors.forename: Guobiao
authors.initials: G
authors.lastname: Ji
authors.affiliation: National Research Center for Veterinary Medicine, Cuiwei Road, High-Tech District, Luoyang, 471003 Henan Province People's Republic of China.
authors.forename: Jinshan
authors.initials: J
authors.lastname: Zhuang
authors.affiliation: OIE Porcine Reproductive and Respiratory Syndrome Reference Laboratory, China Animal Disease Control Center, No. 20 Maizidian Road, Chaoyang District, Beijing, 100125 People's Republic of China.
authors.forename: Xinyan
authors.initials: X
authors.lastname: Zhai
authors.affiliation: College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou, People's Republic of China.|National Research Center for Veterinary Medicine, Cuiwei Road, High-Tech District, Luoyang, 471003 Henan Province People's Republic of China.|OIE Porcine Reproductive and Respiratory Syndrome Reference Laboratory, China Animal Disease Control Center, No. 20 Maizidian Road, Chaoyang District, Beijing, 100125 People's Republic of China.
authors.forename: Kegong
authors.initials: K
authors.lastname: Tian
keywords: HNjz15; HNyc15; NADC30-like; PRRSV; Recombination