Neanderthal Viruses Found in Modern Humans
Kelley Monaghan (12:00 Micro) found an article from Science Daily about a genetic sequence from a Neanderthal that is shared by modern humans. What makes this sequence particularly interesting is that it is a viral sequence that became incorporated into the genome as a provirus, at some point in human evolution where humans and Neanderthals shared a common ancestor. Here is Kelley’s summary:
Researchers at both Oxford University and Plymouth University recently discovered that in modern DNA there is an ancient virus that dates back to the Neanderthals. They came up with the theory that roughly half a million years ago this virus originated in our human ancestors. This was proven when researchers compared a cancer patient’s genetic data from modern day to the genetic data of fossils from both human ancestors the Neanderthals and Denisovans. Scientist plan to look into the relationship between modern diseases and ancient viruses could even help further our knowledge of the diseases such as cancer and HIV, and make us one step closer to finding the cure.
Endogenous retroviruses are simply viruses from our DNA sequence that can be passed down from one generation to the next generation, and they make up eight percent of our DNA. Scientists clump endogenous retroviruses into “junk” DNA, which has no known function yet and makes up 90% of our DNA. Medical Research Council (MRC) member Dr Gkikas Magiorkinis of Oxford University’s Department of Zoology say that, “’I wouldn’t write it off as “junk” just because we don’t know what it does yet,” concerning the recent discoveries. He believes this because under some circumstances disease has been caused from the combination of two “junk” viruses. This isn’t a new concept; we have seen this before in animals. For example, in mice endogenous retroviruses when activated by bacteria can lead to cancer. Dr Gkikas and his colleagues at Oxford University’s Department of Zoology have been studying the possible link between these ancient viruses to cancer and HIV. The link may be from the ancient viruses being apart of the HML2 family for viruses. Dr Gkikas and his colleagues are testing to see in humans today if these ancient viruses are active or the cause of diseases. To conduct these tests they are going to use 300 patients’ DNA sequences in order to see how common these ancient viruses are in the modern day human population. Dr Rober Belshaw, who is a former Oxford University staff member and currently at Plymouth University, said, “We would expect viruses with no negative effects to have spread throughout most of the modern population, as there would be no evolutionary pressure against it. If we find that these viruses are less common than expected, this may indicate that the viruses have been inactivated by chance or that they increase mortality, for example through increased cancer risk.”
Without the modern day technology, none of this research would have ever been able to happen. And, hopefully there will be upcoming technological breakthroughs that will be able to further fuel this research. Researchers are planning to see these technological advances as soon as 2014! They are hoping to have some solid proof for the connection between ancient viruses and modern human diseases, and what role the ancient viruses are playing concerning out modern day diseases within the next five years.