Development and Application of an RT-PCR to Differentiate the Prevalent NA-PRRSV Strains in China

Yanlin Li1, 2, #, Guobiao Ji2, #, Xiaodong Xu1, 2, Juan Wang2, Yingying Li2, Feifei Tan2, Xiangdong Li2, *
1 College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou, China
2 National Research Center for Veterinary Medicine, Luoyang, China

© 2017 Li et al.

open-access license: This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International Public License (CC-BY 4.0), a copy of which is available at: This license permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

# These authors contributed equally to this study.* Address correspondence to this author at the National Research Center for Veterinary Medicine, Luoyang, China; Tel: +86-379-60687971; Fax: +86-379-60687996; E-mail:



PRRSV features with genetic diversity and high mutation which leads to the emergence of a multiple of circulating virus strains with different virulence. North American (genotype 2) PRRSV (NA-PRRSV) can be divided into classical PRRSV (C-PRRSV), highly pathogenic PRRSV (HP-PRRSV), and NADC30-like PRRSV (NL-PRRSV) according to their genomic characteristics and pathogenicity. So far, the above three subtypes of NA-PRRSV are now circulating in China.

Objective and Method:

In this study, a reverse transcript polymerase chain reaction (RT-PCR) was established to simultaneously differentiate three subtypes of NA-PRRSV. The established RT-PCR can be applied to PRRSV-infected samples originated from both supernatant of cell culture and pig tissues and showed specificity exclusively to PRRSV. The sensitivity of RT-PCR showed the minimum RNA detection was 0.04ng/µl.

Result and Conclusion:

The established RT-PCR was next used to differentiate the subtypes of 29 NA-PRRSV isolated in 2016 and the results showed that HP-PRRSV is still the dominant circulating virus strain in the presence of NADC30-like PRRSV in Henan province.

Keywords: PRRSV, North American genotype, HP-PRRSV, NADC30-like PRRSV, RT-PCR.