I wonder if this is a press release. There's nothing at Nature yet.
It might be there.
"The research, which appeared online today in Nature, offer the first evidence of such non-retroviral sequence incorporation into mammalian genomes and suggests bornaviruses infected some mammalian species tens of millions of years ago."
http://www.genomeweb.com/sequencing/mammalian-genomes-house-non-retroviral-rna-virus-sequences-study-finds
"Researchers report in this week's issue of Nature that bornaviruses, a group of negative sense RNA viruses, integrated into the DNA of humans and other primates, rodents, and elephants millions of years ago."
http://www.the-scientist.com/blog/display/56239/