Wasn't sure whether to post under Alzheimer's (doesn't mention it but viruses come up in our discussions pro and con), or Other.
"The finding backs the controversial idea that viruses which took up residence in our DNA millions of years ago may be playing the role of puppet master, quietly influencing our existence and evolution. "We are creatures controlled by viruses," says Luis Villarreal of the University of California at Irvine."
"'It's as if retroviruses are competing with each other via their human host.'"
"These viruses have the genetic tools to refashion the hosts' genes, influencing which are active and when, and with which other genes they interact. This means they have the ability to reshape the physical characteristics of their hosts, says Villarreal. 'It's a massive dynamic pool of colonising genomes.'"
"About 9 per cent of our genome is thought to have come about this way. "