Covid-19, The Longstanding Human-Virus Connection, and how Viruses Make Our Lives Possible?
The world right now is scrambling to fight the dreaded Coronavirus(Covid-19) and limit the number of deaths which it is capable of leaving in its wake. But, according to Jan Carette from Stanford University, there is a fair amount of ‘virus material’ embedded in our genetic code that invading viruses have left behind as parting gifts over the millions of years of human history. The human genome contains about 1 lakh known fragments of virus genetic material i.e. 8% of our DNA consists of viral DNA sequences. But, it is a well-known fact that the human body contains scores of microorganisms that have little to no effect on our lives. So, is the virus DNA just ‘along for the ride’ in our bodies?
COVID-19 Not quite. Studies have indicated that ancient virus genes that began to integrate in our DNA millions of years ago may actually play a much bigger and necessary role in our lives, insofar as to say that the human race would not exist as it does today without viruses. When a human embryo is only 3-days old, and only contains 8 cells, it contains genes derived from its parents as well as the proteins belonging to the ancient HERVK (Human Endogenous Retrovirus-K), which left its mark on our DNA 2 lakh years ago. These viral proteins protect the vulnerable embryo from other, more harmful viral proteins like those belonging to the Influenza (flu) virus, and possibly even COVID-19.
Not only that, but the very biological apparatus that allows nutrients to be transferred from mothers to their unborn babies, the placenta, form without the presence of a viral protein called syncytin. This protein initially allowed viruses to connect host cells so that they could replicate and infect organisms faster. But now it allows babies to form a physical connection with their mothers. When this protein is not present, human survival past the embryo stage is thought to be impossible. In fact, genes borrowed from these single-celled viruses are what allow for the existence of multicellular organisms. Without them, cells might not have the ability to grow into complex tissues and organs, according to New Scientist.
Evidently, these ancient footprints left COVID-19 behind by the primordial viruses that killed many of our ancestors are now irreplaceable for our survival and continued existence. Could they also prove to be an effective tool in our arsenal against the dreaded coronavirus? Only time, and research, will tell…