2016-2017年我国华北地区猪繁殖与呼吸综合征病毒类NADC30毒株分子遗传演化分析

为了解我国华北地区类NADC30流行猪繁殖与呼吸综合征病毒(PRRSV)及遗传变异情况,本研究自2016~2017年采集华北四省市(北京、天津、山东及河北)部分猪场疑似PRRSV样品239份进行RT-PCR检测,对所有阳性样品的ORF5基因测序分析及部分阳性样品病毒分离,并选择1株基因缺失病毒TJjh1602株进行全基因的序列扩增及分析.结果显示:PRRSV检测总阳性率44.35%(106/239),遗传进化显示52.83%(56/106)的流行毒株与类NADC30相近且位于系谱1(lineage 1),其中32.14%(18/56)的类NADC30流行毒株具有相同特征性的氨基酸位点缺失;TJjh1602株全基因长度为15018 nt,与NADC30同源性为95.2%,除具有上述特征性氨基酸位点缺失外,无其他插入或缺失.研究结果推测PRRSV类NADC30毒株在我国华北地区广泛流行,同时已遗传演化成一类具有ORF5缺失分子标签的新型类NADC30毒株,提示需进一步加强对PRRSV新型缺失毒株的流行病学调查及相关致病力研究.

GENETIC VARIATIONS OF NADC30-LIKE PORCINE REPRODUCTIVE AND RESPIRATORY SYNDROME VIRUS FROM 2016 TO 2017 IN NORTH CHINA

To investigate the genetic variations and epidemiology of NADC30-Like Porcine reproductive and respiratory syndrome virus(PRRSV),239 samples collected from 2016 to 2017 in North China(Beijing,Tianjin,Hebei,Shandong)were tested by RT-PCR and ORF5 were sequenced for genetic analysis.The whole genomic sequence of NADC30-Like PRRSV(TJjh1602)was also included for comparison.The results showed that the PRRSV positive rate of these clinical samples was 44.35%(106/236)and 52.83%(56/106)isolates were clustered into lineage 1(NADC30-like strains),in which 32.14%(18/56)isolates contained a unique single amino acid deletion at position 34 of GP5.The full genome of the NADC30-like PRRSV strain(TJjh1602)was 15018 nucleotides and shared 95.2% nucleotide similarity with NADC30.There were no other insertions or deletions.These data demonstrated that the NADC30-like strains with the unique amino acid deletion at position 34 of GP5 were currently prevailing in North China and the biological significance of the novel deletion in NADC30-Like PRRSV strain need to be further studied.