Viruses were traditionally thought to be malicious nanoscopic bearers of death and destruction. But modern science has suggested that while that is sometimes the case, the relationship between viruses and living organisms is a complicated one, as is the question of whether viruses can be truly considered "living" organisms. I. Viruses Can Actually be Useful, Sometimes In case newly discovered mega-viruses -- which rival small bacteria in size, function, and genetic complexity (and are sometimes "infected" by other viruses) -- aren't mind-warping enough, recent evidence suggests that as much of 8 percent of the genetic material found in higher organisms such as humans may be "borrowed" from viral genomes. These pieces of DNA are identifiable, if you know what you're looking for, but long ago lost their ability to depart and jump to new hosts. In that regard, mankind can be viewed as similar in some ways to lichen -- as a collection of multiple fused "organisms" living as one -- as modern man's genetic code consists of virus and traditional eukaryotic genes functioning side by side. The latest wild discovery comes courtesy of Montreal, Quebec, Canada's McGill University.

Professor Bourque states in an interview with National Geographic:

[Acquiring useful genes from viruses] can be faster than just relying on random mutations to get something that might work.

[These genes should be examined] to see if they have also evolved new functional roles, like HERV-H did in stem cells. We suspect that these genes may play important roles in other cell types as well, such as liver, kidney, and brain.

Sources: NATURE STRUCTURAL & MOLECULAR BIOLOGY, National Geographic

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Primate Stem Cell Creation Appears Driven by Genes From Ancient Virus