Copy Number Variant Analysis of Porcine Endogenous Retrovirus (PERV) in the Genome of Vietnamese Native Pigs

Xenotransplantation of pig organs to human has been hoped to make up the shortage of life-saving organ transplants. However, pig genome is riddled with many copies of porcine endogenous retrovirus (PERV) which may cause a potential risk of producing infectious viral particles in the recipient. There have been a few studies examined copy number variation in PERVs suggesting that Asian pigs might have less copies of PERV than those of Western breeds. Therefore, we aimed to survey PERVs in the genome of native pigs in Vietnam, where it is expected to be one of pig domestication centers. Fifteen native pig breeds from far and wide areas of the country were used to obtain genomic DNAs. We previously elucidated that two of native pig breeds tended to show weaker PCR amplification of pol gene in PERV-A, B and C compared to those of the other breeds. Additionally, six breeds showed fewer env gene in PERV-A and B. Interestingly, env gene in PERV-C was not detected in all breeds. In this study, we carried out measurements of PERV copy number using a real-time PCR-based method targeting pol, gag and env genes in PERV-A, B and C normalized by β-actin gene. The results of this study suggested several Vietnamese native pig breeds showed fewer copies of infectious PERV-A and B than average copy numbers. We anticipate that in the future those breeds may be a candidate for medical model. Detail of the latest findings will be represented in the poster session.