title: Molecular mutations associated with the in vitro passage of virulent porcine reproductive and respiratory syndrome virus.
abstract: Mutants of a highly pathogenic, porcine reproductive, and respiratory syndrome virus (PRRSV), JXA1 strain, were prepared by continuous in vitro passage. Genomic sequence comparisons were made between mutants obtained at different passages and the parental strain JXA1. The mutant strain obtained at passage 80 contained a 12 nucleotide insertion and 108 nucleotide mutations that resulted in 45 amino acid changes. Most of these changes (89%) occurred between passage 10 and 45 and were genetically stable for the next 35-70 passages. A comparison of the mutants, their parental strain, and several American PRRSV strains, identified 13 characteristic amino acid changes. These sites, as well as the distinct 12 nucleotide insertion, represent possible genetic markers for the evaluation of live vaccine applications, particularly for additional studies of the safety and potency of live PRRSV vaccines.
authors.affiliation: College of Veterinary Medicine, China Agricultural University, No. 2 Yuanmingyuan Western Road, Haidian District, Beijing, People's Republic of China.
authors.forename: Wei
authors.initials: W
authors.lastname: Han
authors.forename: Jia-Jun
authors.initials: JJ
authors.lastname: Wu
authors.forename: Xiao-Yu
authors.initials: XY
authors.lastname: Deng
authors.forename: Zhen
authors.initials: Z
authors.lastname: Cao
authors.forename: Xiu-Ling
authors.initials: XL
authors.lastname: Yu
authors.forename: Chuan-Bin
authors.initials: CB
authors.lastname: Wang
authors.forename: Tie-Zhu
authors.initials: TZ
authors.lastname: Zhao
authors.forename: Nan-Hua
authors.initials: NH
authors.lastname: Chen
authors.forename: Hong-Hui
authors.initials: HH
authors.lastname: Hu
authors.forename: Wang
authors.initials: W
authors.lastname: Bin
authors.forename: Li-Li
authors.initials: LL
authors.lastname: Hou
authors.forename: Li-Lin
authors.initials: LL
authors.lastname: Wang
authors.forename: Ke-Gong
authors.initials: KG
authors.lastname: Tian
authors.forename: Zhong-Qiu
authors.initials: ZQ
authors.lastname: Zhang
mesh_terms: D000220:Adaptation, Biological; D000595:Amino Acid Sequence; D000818:Animals; D002460:Cell Line; D002522:Chlorocebus aethiops; D004252:DNA Mutational Analysis; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional; D009154:Mutation; D020125:Mutation, Missense; D017354:Point Mutation; D019316:Porcine respiratory and reproductive syndrome virus / Q000235:genetics* / Q000472:pathogenicity*; D012367:RNA, Viral / Q000235:genetics; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D012692:Serial Passage
chemical_list: D012367:RNA, Viral