Remnants of ancient viral DNA are still active in the genomes of animals alive today. At some point in evolutionary history, many of these so-called endogenous retroviruses inserted themselves into the DNA of their host, and their genetic code has been present ever since. Studies have found that this leftover DNA still serves crucial roles unique to mammals.
In a study published in Development on September 26, scientists say they’ve characterized two retrovirus-derived genes that fight infections in the brains of mammals that give birth to live young, a group known as eutherians.
Study coauthor Tomoko Kaneko-Ishino, a geneticist at Tokai University in Japan, says it took her more than 30 years to uncover the function of two virus-derived genes. In an email to The Scientist, she writes that the new work’s roots extend back to a 1989 study on genomic imprinting, a phenomenon where maternal or paternal genes shut ...
