(Sky News)
The coronavirus pandemic may have been started by stray dogs eating bat meat, according to a study.
Professor Xuhua Xia, from the University of Ottawa’s biology department, has suggested that stray dogs are the most likely intermediate host for the transmission of Sars-CoV-2 into humans.
According to the study, the ancestor of the new coronavirus and its nearest relative – a bat coronavirus – infected the intestines of dogs. They then evolved before moving to humans.
Humans and mammals can fight viruses through an antiviral protein which stops the infection multiplying. Meanwhile, regions of DNA – CpG dinucleotides – tell the immune system to attack the virus.
But single-strand coronaviruses can avoid the body’s natural defences by reducing the CpG.
Prof Xia analysed betacoronavirus genomes and found that Sars-CoV-2 and its closest relative – a bat coronavirus – have the lowest amount of CpG.
Only genomes from canine coronaviruses have similar genomic values, the study says.