Identification and genetic analysis of horse-origin human papillomavirus 23
JIA Chen-yang;TONG Pan-pan;SONG Xiao-zhen;DENG Hai-feng;DUAN Ru-li;PALIDAN Nuerlan;REN Mei-ling;ZHANG Lei;KUANG Ling;XIE Jin-xin;College of Veterinary Medicine, Xinjiang Agricultural University;Zhaosu Horse Barn in Yili;
In order to understand the types of human papillomaviruses(HPV) carried by touring horses in North Xinjiang.Nasal swabs were collected from 52 thoroughbred horses in Yili, 100 thoroughbred horses in Changji, and 30 akhal-teke horses in Urumqi, and the viral metagenomic sequencing was applied to detect the types of HPVs in horses. The resulting metagenomic data of the nasal swabs showed that HPV-23 was present. To confirm the result, HPV-23(GenBank accession numbers: KY652675) E2gene was selected to design specific primers for PCR. The samples were tested with PCR and the results showed the HPV-23positive rates were 16.7%(5/30), 2%(1/52), and 1%(1/100) in nasal swab samples of horses in Urumqi, Yili and Changji,respectively. Those findings indicated that thoroughbred horses and akhal-teke horses were the dominant HPV-23 carries in tourist scenic, and the positive rates of HPV-23 infection were closely related to horse breeds. Sequences analysis indicated that horseorigin HPV-23 E2 gene shared 98.2%-99.4% nucleotide sequence identity and 95.5%-99.1% amino acid sequence identity with E2gene of HPV-23 reference strains in abroad, but shared 44.2%-55.1% nucleotide sequence identity and 18.2%-29.4% amino acid sequence identity with E2 gene of equus caballus papillomavirus(EcPVs). The phylogenetic tree analysis showed that horse-origin HPV-23 and human HPV-23 reference strains have close genetic relationship, but diverging from the lineages of EcPVs and other HPVs. These results suggested that horse-origin HPV-23 might come from human.In this study, horse-origin HPV-23 was identified and genetic evolution analysis was performed based on its E2 gene. These findings provide fundamental data for the epidemiological study of animal-origin HPV-23.