Rome, 23 March (beraking latest news Health) – Men who have a rare genetic variant are at an increased risk of developing severe forms of Covid-19. This is what was discovered by the group of researchers of the University of Siena, authors of a study, published in the journal ‘eLife’, conducted in collaboration with the University of Pavia.
The research – coordinated by Alessandra Renieri, professor of the Department of Medical Biotechnology and head of the Medical Genetics Unit of the Sienese University Hospital – showed how male patients who have a mutation in the TLR7 gene, responsible for regulating the production of interferon on the part of immune cells during viral infection, they are more likely to manifest severe clinical forms of Covid-19, up to admission to intensive care and death. The results – underlines a note from the Sienese university – open the use of interferon for personalized therapies for patients with this genetic variant, to prevent the serious consequences of the disease.
“Although advanced age and the presence of other conditions, such as cardiovascular disease or diabetes, are known risk factors, they alone do not fully explain the differences in severity in the clinical manifestations of Covid-19”, explains Chiara Fallerini, research fellow at the Department of Medical Biotechnology of the University of Siena and first author of the study. “Some men, with no particular pre-existing medical conditions – he continues – are more likely to be hospitalized in intensive care and die from Covid-19, which suggests that other factors are involved in causing a deficit in their immune system”.
Interferon – the Tuscan university still details – is produced by immune cells during viral infection, following the stimulation of sensors called Toll-like receptors (TLRs) that detect viruses and initiate the immune response. “When a recent study identified rare mutations in the TLR7 gene in young men with severe Covid-19 – highlights Mario Mondelli, professor of Infectious Diseases at the Division of Clinical Immunology and Infectious Diseases of the San Matteo Polyclinic and of the University of Pavia – we wanted to investigate if this was a very rare situation or just the tip of the iceberg “.
The research was conducted on a group of 156 male Covid patients under the age of 60, selected within the large multicentre Gen-Covid study, coordinated by Alessandra Renieri, which has involved a network of over 40 Italian hospitals. The team identified the TLR7 gene as one of the most important linked to severe clinical manifestations of the disease. He then selected the youngest male patients aged less than 60 from the entire Gen-Covid database, identifying rare TLR7 mutations in 5 of 79 patients (6.3%) with life-threatening Covid-19 and no mutations in patients who they had few symptoms.
“Our results – says Elisa Frullanti, researcher of the Sienese university group, one of the authors of the study – show that young men with severe manifestations of Covid-19 who have lost the regulatory function of interferon in their genes represent a small but important subgroup of the most vulnerable patients “. “These mutations – concludes Renieri – could potentially explain the severity of the disease in 2% of men with Covid. We therefore believe that genetic screening can help promptly identify cases in which treatment with interferon can be decisive and thus prevent further dead “.