Dogs, humans may have shared viruses
Dogs and humans have shared many things over their 10,000-year relationship. Now it seems that the two species may have shared some genetic material as well, exchanged through the transmission of viruses, according to a new study from Uppsala University in Sweden.
The researchers studied the genome of a female boxer and looked for chains that corresponded to known retroviruses, which can integrate themselves into the genome of their hosts. They found that only 0.15% of the canine genome was made up of these endogenous retroviruses (ERV), compared to about 0.8% in humans and 2% in mice.
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| Looks innocent enough, but humans and dogs may have exchanged genetic material over the millennia via retroviruses. |
Canids may have had fewer retroviral infections than other mammals, the researchers speculate, but there could be other causes for the low percentage.
"However, the paucity of known extant retroviruses in dogs compared to other mammals as well as the current status of the dog assembly and the limited number of carnivore species sequenced to date preclude firm conclusions regarding mechanisms and processes leading to the low [canine endogenous retrovirus] content observed in dog," the study says.
The study says that one group of retroviruses was similar to a human retrovirus, giving rise to the hypothesis that dogs and humans may have shared viruses over the millennia.
"This ERV analysis of the first carnivorous species supports the notion that different mammals interact distinctively with endogenous retroviruses and suggests that retroviral lateral transmissions between dog and human may have occurred," the study concludes.
The report, "The first sequenced carnivore genome shows complex host-endogenous retrovirus relationships," was published in the online journal PLoS One.