COVID-19, caused by SARS-CoV-2 virus infection, has changed human behavior patterns since it became a global pandemic. To date, more than 136 million people have suffered from the disease and, of these, more than 2.9 million have lost their lives. The symptoms of the infection vary widely, from individuals who show no clinical symptoms to those who need admission to the ICU with emergency assisted breathing.

At present, it is still largely unknown what factors are responsible for this diverse range of clinical pictures. Now, an article published today in EBioMedicine — the sister journal of The Lancet for laboratory findings — shows that each person’s epigenetic endowment influences the severity of COVID-19. The work was carried out by the teams led by Manel Esteller, professor of the Department of Physiological Sciences at the UB, director of the Josep Carreras Leukemia Research Institute (IJC) and ICREA research professor, and Aurora Pujol , also an ICREA professor and head of the IDIBELL Neurometabolic Diseases Group.

Due to the high number of people infected with the virus that have saturated all health systems in the world, there should be ways to predict in advance whether the infection in a given individual will require hospitalization or can simply be controlled on an outpatient basis. It is now known that advanced age and the coexistence of other pathologies (cardiovascular, obesity, diabetes, immune defects) is associated with a more severe SARS-CoV-2 infection. But what about the rest of the population? This is the question asked by the researchers: “To do the research we decided to study more than 400 people who had tested positive for COVID-19 and did not belong to any of the risk groups, and we analyzed the genetic material depending on whether they had no symptoms, or were very mild, or whether, on the other hand,

“The results of the study – continues the researcher – show that there are epigenetic variations in the chemical switches that regulate the activity of DNA in the positive ones by the virus that developed severe COVID-19.” These modifications occur primarily in genes associated with an excessive inflammatory response and in genes that reflect a general tendency to have poorer health. “It should be noted that 13% of the world’s population has this epigenetic signature (EPICOVID); therefore, it is the population of maximum risk for which we will have to have a special preoccupation ”, concludes Esteller.