CAMBRIDGE, England, March 13 (UPI) -- Genes will regularly jump ship, linking up with another organism, if given the chance. It's a process known as horizontal gene transfer.
But previously, scientists believed this was mostly a strategy of smaller organisms. A new study, however, suggests natural transgenics is equally common among larger species like humans. In fact, it's now clear that humans regularly swap genes with the germs they host and the plants they eat.
"This is the first study to show how widely horizontal gene transfer occurs in animals, including humans, giving rise to tens or hundreds of active 'foreign' genes," explained lead author Alastair Crisp, a researcher in chemical engineering and biotechnology at the University of Cambridge.
"Surprisingly, far from being a rare occurrence, it appears that this has contributed to the evolution of many, perhaps all, animals and that the process is ongoing," Crisp said. "We may need to re-evaluate how we think about evolution."
Researchers analyzed the genomes of several dozen species, including several types of fruit fly, nematode worm, and primate, including humans. After comparing genomes of similar species, scientists were able to isolate genes most likely to have come from foreign origins.
Scientists found at least 145 genes likely to have been acquired via horizontal gene transfer, only 17 of which had been previously identified. Many of these genes are believed to be involved in metabolic processes, but many more have an undefined purpose. Bacteria and protists, a class of microorganisms, are pegged as the most frequent donors, but fungi and plants have also shared their genes readily.
Researchers say it's likely their study actually underestimates natural trangenics among species. Even so, they say just one percent of the human genome is made up of transferred genes.
The study was published this week in the journal Genome Biology.
