This gene, which is a member of the "mucin" family, contributes to the creation of mucus, which lubricates and protects the airways.
The frequency of gene "MUC22" mutations was twice as common in the moderate Covid-19 group as it was in the severe patients, and even more prevalent in resilient super-agers.
Excessive mucus production has been connected to the severe lung inflammation that characterises severe Covid-19.
They found that mutations in MUC22 are technically termed "missense" variants.
A group of Brazilian researchers have found a gene that can protect people—even those over 90—from the deadly coronavirus disease. According to two research papers, the frequency of gene "MUC22" mutations was twice as common in the moderate Covid-19 group as it was in the severe patients, and even more prevalent in resilient super-agers.
This gene, which is a member of the "mucin" family, contributes to the creation of mucus, which lubricates and protects the airways, reports IANS.
While on the other hand, excessive mucus production has been connected to the severe lung inflammation that characterises severe Covid-19. One research paper involved a group of resilient older people aged 90 or more, while the other examined a case of severe Covid-19 in identical twins, only one of whom experienced the disease's long-term effects.
"If we can really prove that some genes promote resistance to SARS-CoV-2, the same may also be true for other viruses. More research can then be based on these findings to try to understand the mechanisms underlying this resilience and develop medications that enhance protection against viral infections," said Mayana Zatz, professor of Human and Medical Genetics at the University of Sao Paulo and lead author of the articles published in the journal Frontiers in Immunology, told Agencia FAPESP.
A cohort of 87 "resilient super-agers" (patients over 90) who recovered from moderate Covid-19 or remained asymptomatic after testing positive for SARS-CoV-2 was examined by researchers in one study. Their average age was 94. The oldest patient in Brazil to have recovered from the illness at the time of the study was a woman who was 114 years old.
They found that mutations in MUC22 are technically termed "missense" variants -- DNA changes that result in different amino acids being encoded at particular positions in the resulting proteins. Moreover, according to the article, they may decrease the hyperactive immune response to the COVID-19 virus and play an important role in defending the airways against the virus. One of the hypotheses entertained by the authors is, therefore, that the resilient subjects may have optimal control of mucin production.
"It may be the case that the missense variants interfere with not only mucus production but also its composition since amino acids are switched. We need to conduct more studies to understand how they act during infections and in healthy people," said Erick Castelli, a researcher at Sao Paulo State University's Medical School.