title: Design and testing of multiplex RT-PCR primers for the rapid detection of influenza A virus genomic segments: Application to equine influenza virus.
abstract: The avian influenza A virus causes respiratory infections in animal species. It can undergo genomic recombination with newly obtained genetic material through an interspecies transmission. However, the process is an unpredictable event, making it difficult to predict the emergence of a new pandemic virus and distinguish its origin, especially when the virus is the result of multiple infections. Therefore, identifying a novel influenza is entirely dependent on sequencing its whole genome. Occasionally, however, it can be time-consuming, costly, and labor-intensive when sequencing many influenza viruses. To compensate for the difficulty, we developed a rapid, cost-effective, and simple multiplex RT-PCR to identify the viral genomic segments. As an example to evaluate its performance, H3N8 equine influenza virus (EIV) was studied for the purpose. In developing this protocol to amplify the EIV eight-segments, a series of processes, including phylogenetic analysis based on different influenza hosts, in silico analyses to estimate primer specificity, coverage, and variation scores, and investigation of host-specific amino acids, were progressively conducted to reduce or eliminate the negative factors that might affect PCR amplification. Selectively, EIV specific primers were synthesized with dual priming oligonucleotides (DPO) system to increase primer specificity. As a result, 16 primer pairs were selected to screen the dominantly circulating H3N8 EIV 8 genome segments: PA (3), PB2 (1), PA (3), NP (3), NA8 (2), HA3 (1), NS (1), and M (2). The diagnostic performance of the primers was evaluated with eight sets composing of four segment combinations using viral samples from various influenza hosts. The PCR results suggest that the multiplex RT-PCR has a wide range of applications in detection and diagnosis of newly emerging EIVs. Further, the proposed procedures of designing multiplex primers are expected to be used for detecting other animal influenza A viruses.
authors.affiliation: Viral Disease Division, Animal and Plant Quarantine Agency, 175 Anyang-ro, Manan-gu, Anyang-si, Gyeonggi-do, Republic of Korea.
authors.forename: EunJung
authors.initials: E
authors.lastname: Lee
authors.affiliation: Viral Disease Division, Animal and Plant Quarantine Agency, 175 Anyang-ro, Manan-gu, Anyang-si, Gyeonggi-do, Republic of Korea.
authors.forename: Eun-Ju
authors.initials: EJ
authors.lastname: Kim
authors.affiliation: Viral Disease Division, Animal and Plant Quarantine Agency, 175 Anyang-ro, Manan-gu, Anyang-si, Gyeonggi-do, Republic of Korea.
authors.forename: Yeun-Kyung
authors.initials: YK
authors.lastname: Shin
authors.affiliation: Viral Disease Division, Animal and Plant Quarantine Agency, 175 Anyang-ro, Manan-gu, Anyang-si, Gyeonggi-do, Republic of Korea. Electronic address: songjysong@korea.kr.
authors.forename: Jae-Young
authors.initials: JY
authors.lastname: Song
mesh_terms: D000818:Animals; D003198:Computer Simulation; D017931:DNA Primers; D016679:Genome, Viral; D006734:Horse Diseases / Q000175:diagnosis / Q000821:virology; D006736:Horses; D006801:Humans; D053123:Influenza A Virus, H3N8 Subtype / Q000235:genetics / Q000302:isolation & purification; D009980:Influenza A virus / Q000235:genetics* / Q000302:isolation & purification*; D007251:Influenza, Human / Q000175:diagnosis / Q000821:virology; D060885:Multiplex Polymerase Chain Reaction / Q000191:economics / Q000379:methods*; D009976:Orthomyxoviridae Infections / Q000175:diagnosis / Q000662:veterinary* / Q000821:virology; D010802:Phylogeny
chemical_list: D017931:DNA Primers
keywords: Dual priming oligonucleotide (DPO); Equine influenza virus; H3N8; Influenza A virus; Multiplex RT-PCR; Phylogenetic analysis; Reverse transcription polymerase chain reaction (RT-PCR)