Viral Influencers: How Ancient Retroviruses Shaped Our Genome

The human genome is like a time capsule, preserving traces of viral infections from millions of years ago. Among these remnants are about 5,000 endogenous retroviral elements called LTR12 repeats. Their role has remained a mystery—until recently.

In our new mini-review, we describe how these ancient retroviral sequences shape cellular gene expression. Despite their repetitive nature, LTR12 elements are far from redundant. They contribute to multiple biological processes, including antiviral immunity, tumor growth, and cellular aging. We also discuss the epigenetic mechanisms that keep these elements silent—or, in some cases, activate them. If you're intrigued by the idea that ancient viruses continue to influence our biology today, you can read more in our review, published in the Journal of Virology, here.

Image (provided by Yueshuang Lu): Endogenous retroviruses have long been disregarded as “junk DNA”. However, at least some of them, including LTR12 repeats, play important physiological roles in humans.