Retroviruses are a group of viruses some of which are dangerous while others are harmless. Some retroviruses exist incorporated in the human genome for millions of years.
A group of these viruses referred to as endogenous retroviruses (ERV) have been studied in the current research at the University in Sweden. They are a part of the DNA which was earlier considered non-essential, so called junk DNA. Researchers have now started reconsidering this notion.
They found that many thousands of ERV established in our genome may act as “docking platforms” for a protein named TRIM28. This protein can “switch off” viruses and the standard genes alongside them in the DNA helix. Thus, ERV’s presence affects gene expression.
This switch-off mechanism differs in individuals as the retrovirus’ placement in the genome differs. This makes it a potential tool for evolution; and a potential causative agent of neurological diseases. Studies show a deviating regulation of ERV in schizophrenia, ALS and bipolar disorder.
"However, if endogenous retroviruses affect brain function, and we have our own set of these ERV, the mechanisms they affect may have contributed to the development of the human brain," says Johan Jakobsson, the study lead.
Content Source: https://www.sciencedaily.com/releases/2017/01/170112110840.htm