[Molecular characterization of the ORF5 (GP5) gene from porcine reproductive and respiratory syndrome virus (PRRSV) detected in pig farms in Lima, Peru].

The porcine reproductive and respiratory syndrome (PRRS) is an endemic disease in pork-producing regions of the world, and its control remains poor. Rapid identification of PRRSV-1 and PRRSV-2 species is of great importance for molecular epidemiological surveillance of the virus. The objective of this study was the molecular characterization of the ORF5 gene that synthesizes glycosylated protein 5 (GP5) from PRRS virus detected in pig farms in Lima, Perú. One hundred serum samples were used, obtaining 24 PRRSV-2-positive strains confirmed by two molecular techniques. Phylogenetic inference demonstrated the parental relationship with the NADC34 variant, and we achieved a better phylogenetic relationship of the study strains with Peruvian reference isolates in lineage 1 and sublineage 1.5 and pathogenic strains from various parts of the world. Homology analysis showed that strains 25 to 35, 40 to 41, and 43 to 48 obtained high nucleotide homology values of 95-98% and amino acid homology of 92-98%; strains 36, 37, 38, and 39 with high genetic variability with low nucleotide homology values of 83% and amino acid homology of 79%, and strain 42 with homology of 89 and 84% in relation to the NADC34 variant. In conclusion, we demonstrated the effectiveness of the validated in-house primers for identification compared to a commercial kit, in addition to the evolution and dispersion of lineage 1, sublineage 1.5 and the phylogenetic relationship with the NADC34 variant of the PRRSV-2 species in Lima, Perú.