Choi Eun-Jin, Lee Chang-Hee, Song Jae-Young, Song Hee-Jong, Park Choi-Kyu, Kim Byounghan, Shin Yeun-Kyung
Animal and Plant Quarantine Agency, Ministry of Agriculture, Food and Rural Affairs, Anyang 430-757, Korea.
J Vet Sci. 2013;14(2):115-24. doi: 10.4142/jvs.2013.14.2.115. Epub 2013 Apr 30.
The high genetic diversity of porcine reproductive and respiratory syndrome virus (PRRSV) has been an obstacle to developing an effective vaccine for porcine reproductive and respiratory syndrome (PRRS). This study was performed to assess the degree of genetic diversity among PRRSVs from Korean pig farms where wasting and respiratory syndrome was observed from 2005 to 2009. Samples from 786 farms were tested for the presence of PRRSV using reverse transcription PCR protocol. A total of 117 farms were positive for type 1 PRRSV while 198 farms were positive for type 2. Nucleotide sequences encoding the open reading frame (ORF) 5 were analyzed and compared to those of various published PRRSV isolates obtained worldwide. Sequence identity of the ORF 5 in the isolates was 81.6˜100% for type 1 viruses and 81.4˜100% for type 2 viruses. Phylogenetic analysis of the ORF 5 sequences showed that types 1 and 2 PRRSVs from Korea were mainly classified into three and four clusters, respectively. The analyzed isolates were distributed throughout the clusters independent of the isolation year or geographical origin. In conclusion, our results indicated that the genetic diversity of PRRSVs from Korean pig farms is high and has been increasing over time.
猪繁殖与呼吸综合征病毒（PRRSV）的高遗传多样性一直是开发针对猪繁殖与呼吸综合征（PRRS）有效疫苗的障碍。本研究旨在评估2005年至2009年期间在韩国猪场观察到消瘦和呼吸综合征时，PRRSV之间的遗传多样性程度。使用逆转录PCR方法对来自786个猪场的样本进行PRRSV检测。共有117个猪场的1型PRRSV呈阳性，198个猪场的2型PRRSV呈阳性。对编码开放阅读框（ORF）5的核苷酸序列进行分析，并与全球范围内已发表的各种PRRSV分离株的序列进行比较。1型病毒分离株中ORF 5的序列同一性为81.6%至100%，2型病毒为81.4%至100%。ORF 5序列的系统发育分析表明，来自韩国的1型和2型PRRSV主要分别分为三个和四个簇。分析的分离株分布在各个簇中，与分离年份或地理来源无关。总之，我们的结果表明，韩国猪场PRRSV的遗传多样性很高，并且随着时间的推移一直在增加。
