Humans carry in their genome the relics of an animal virus that infected their forerunners at least 40 million years ago, according to research published Wednesday by the British science journal Nature.
The invader is called bornavirus, a brain-infecting pathogen that was first identified in 1970s.
Scientists led by Keizo Tomonaga of Japan’s Osaka University compared the DNA of a range of mammals, including humans, apes, elephants, marsupials and rodents, to look for tell-tale signatures of bornavirus code.
In the human genome, the team found several bornavirus fragments but also in the form of two genes that may be functional, although what they do is unclear.
Until now, the only viruses known to have been handed on in vertebrates were retroviruses, which work by hijacking cellular machinery in order to reproduce.
Retroviruses are effective in infiltrating the germline — the DNA of reproductive cells, which means their sequence, or part of it, is handed on to ensuing generations.
By some estimates, retroviruses account for as much as eight percent of the human code for life. Bornavirus has a different stealth tactic, replicating in the nucleus of infected cells.
The disease owes its name to the German town of Borna, where a regiment of cavalry horses was wiped out in 1885 by a mysterious “heated head” disease. Later research also found the disease among sheep, llamas, ostriches, cats and cattle, although how it spreads is poorly understood.
The impact of bornavirus on the human genetic odyssey is likely to trigger fierce debate.
The big questions are whether it provided a potential cause of genetic mutation or innovation in our species, or whether it provided a source for inherited illness — or, conversely, protection. Bornavirus has not been clearly linked to diseases in humans, although some researchers speculate there could be a link with schizophrenia and other mental disorders.
via Viral phenomenon: Ancient microbe invaded human DNA – Yahoo! News.
“I’d like to share a revelation that I’ve had during my time here. It came to me when I tried to classify your species and I realized that you’re not actually mammals. Every mammal on this planet instinctively develops a natural equilibrium with the surrounding environment but you humans do not. You move to an area and you multiply and multiply until every natural resource is consumed and the only way you can survive is to spread to another area. There is another organism on this planet that follows the same pattern. Do you know what it is? A virus. Human beings are a disease, a cancer of this planet. You’re a plague and we are the cure.” – the matrix
Woah! Mr. Smith was right! We really are part virus. This explains so much, especially if some of those other mental disorders make us invade, use all available resources and reproduce irresponsibly.
Perhaps some people have less viral DNA influencing their brains than others… 😉 Wouldn’t it be great if we could just remove that viral code and become a whole new species, the species we should really be? What do you imagine that would be like?