Spanish and Dutch scientists revealed two new mutations in the TLR7 gene in healthy young men who are sick of the heavy form of COVID-19. As researchers write in an article published in the journal Frontiers in Immunology, mutations are able to undermine immune defense, making a person more susceptible to coronavirus.
It is already known that mutations in the TLR7 gene can be a rare genetic risk factor for heavy COVID-19. Previously, the researchers reported that two unrelated pairs of the brothers were seriously ill with coronavirus, and one of them died. Everyone had a mutation in the TLR7 gene, which encodes the receptor, important to recognition of the coronavirus and initiating an antiviral immune response through the induction of interferon. Thus, this gene serves as an important protection factor for SARS-COV-2.
Italian study, in which men participated over 60 years old with the severe form of COVID-19, showed that more than two percent of seriously sick patients carry a genetic mutation in TLR7. This leads to a violation of the functioning of the corresponding receptor. Scientists observed the difficult activation of the transfer of interferon signals, as a result of which the optimal immune response could not develop.
In a new study, experts analyzed 14 cases of severe COVID-19 in young men under the age of 50. Unknowns have been identified until now the mutations of the TLR7 gene, and in one patient, the resident of the Netherlands, the defective activation of the transmission of signals and the disruption of interferon production was again observed. At the same time, two cousins of the Dutch patient who have not yet been exposed to coronavirus, the same mutation was discovered. To reduce the risk of serious illness, they passed preventive vaccination.