Science for children: Covid-19 and genetics

You've probably already heard about the virus that forces us to wear a mask very often and to be particularly careful to wash our hands well? The reason why we take so many precautions is that some people are particularly vulnerable to this virus, for a whole bunch of different reasons. Sometimes we don't know why some people have very severe symptoms.

Published on 15.02.2021


That's why researchers around the world are trying to understand what's happening to these patients. Especially here in Paris at the Imagine Institute, research labs have been helping to find explanations! To do this, researchers have gone to explore the DNA of seriously ill patients.

DNA is the instruction manual that allows us to create living beings, like humans for example. Everyone carries it within themselves, it is microscopic, but it is full of very useful information for our bodies. It is written on the DNA what color our eyes and skin are, how to build our bones etc... In the DNA, it is also written what our body can do to defend itself against microbes: create sentinels that circulate in the body to spot intruders, produce messengers to warn our lines of defense and ask for help from virus neutralizers for example...

Researchers have recently shown that in some people who are very sick with COVID-19, there are changes in the parts of the DNA that produce what are called Type 1 Interferons (IFN1). These interferons are a family of molecules that normally act as messengers on our cells, prompting them to defend themselves against viruses. The problem is that because these interferons are not present in some patients, their cells don't build up their defenses as well as they should, and the virus can continue to cause damage in their bodies. 

Understanding these mechanisms allows us to propose strategies for predicting who is likely to have severe symptoms. Indeed, physicians now know a little better where to look for this information in patients' DNA. Above all, understanding these mechanisms makes it possible to imagine treatment strategies! For example, to compensate for the lack of interferons, there are already known treatments that make it possible to give interferons to patients via an injection, for example.

Finally, interferon "blocking" antibodies only target certain members of this family of molecules. Thus, we can imagine that to compensate for the action of these autoimmune antibodies, we can give patients more interferons that are not targeted by the "blockers": this drug already exists because it has been developed for other diseases, and should be tested. All this is still at the hypothesis stage, but these theories are very promising to succeed in curing some COVID-19 patients!

It may seem easy to find all these answers. However, part of the reason that researchers have been able to understand why some people get very sick from COVID-19 is because they already knew how our body's defenses against microbes work! This is particularly true when studying certain genetic diseases that are also caused by changes in DNA or the presence of "blocking" autoimmune antibodies.

The Imagine Institute aims to understand genetic diseases that can be very rare. Understanding these diseases thus sometimes makes it possible to elucidate much more widespread health problems, such as COVID-19, for example.

To learn more about researchers' discoveries on severe forms of Covid-19