A recent study revealed 19 new pieces of nonhuman DNA inside modern humans’ genomes. The March 22 finding comes after researchers from Tufts and University of Michigan Medical School examined 2,500 people.
The nonhuman DNA is reportedly left from viruses that resided in humans’ genetic ancestors thousands of years ago, reports NH Voice.
Researchers are unsure of implications to those carrying the viral DNA, or whether it can replicate.
“Many studies have tried to link these endogenous viral elements to cancer and other diseases, but a major difficulty has been that we haven’t actually found all of them yet,” said researcher Zachary H. Williams of the Tufts Sackler School of Graduate Biomedical Sciences.
The study shed new light on human endogenous retroviruses, reports Science Daily. HERVs are ancient diseases with similar characteristics to human immunodefiency virus, the pre-cursor to AIDS.
The viral DNA has reportedly been passed down through thousands of generations of humans. As of now, the study’s authors are unsure of whether the ancient strains of DNA could cause infections.
“This one looks like it is capable of making infectious virus, which would be very exciting if true, as it would allow us to study a viral epidemic that took place long ago,” said co-author John Coffin, of the Tufts University School of Medicine.
“This research provides important information necessary for understanding how retroviruses and humans have evolved together in relatively recent times.”
Researchers say the study will boost researchers’ understanding of DNA-based viruses.
“This is a thrilling discovery. It will open up many doors to research,” said co-author Julia Wildschutte of Tufts University.
“What’s more, we have confirmed in this paper that we can use genomic data from multiple individuals compared to the reference human genome to detect new HERVs. But this has also shown us that some people carry insertions that we can’t map back to the reference.”