Did you know your DNA is about five percent virus?
It’s true. Scientists have long known that endogenous (having an internal cause or origin) retroviruses, millions of years old, make up five percent of our DNA. They had assumed this was just junk data, an evolutionary oddity, because viruses, amiright?
But researchers have recently discovered it’s not junk at all, and might actually play a central role in building up the networks of our brains. Lund University’s Johan Jakobsson and his colleagues say the retroviruses seem to work to regulate which genes are expressed and when.
Jakobson’s findings are based on a study of neural stem cells, which looked at the molecular mechanism the cells use to control the activation of the retroviruses.
“We have been able to observe that these viruses are activated specifically in the brain cells and have an important regulatory role. We believe that the role of retroviruses can contribute to explaining why brain cells in particular are so dynamic and multifaceted in their function. It may also be the case that the viruses’ more or less complex functions in various species can help us to understand why we are so different”, said Jakobsson, head of the research team for molecular neurogenetics at Lund University.
Jakobson hopes understanding the viruses will create a more complete picture of the brain to guide treating diseases.
“I believe that this can lead to new, exciting studies on the diseases of the brain. Currently, when we look for genetic factors linked to various diseases, we usually look for the genes we are familiar with, which make up a mere two per cent of the genome. Now we are opening up the possibility of looking at a much larger part of the genetic material which was previously considered unimportant. The image of the brain becomes more complex, but the area in which to search for errors linked to diseases with a genetic component, such as neurodegenerative diseases, psychiatric illness and brain tumours, also increases,” Jakobson said.
[Source: Lund University]