According to a study published in the journal Frontiers in Immunology, researchers have discovered a gene that can protect people, even those aged 90 and older, from the deadly COVID disease. In the meta-analysis study, a team of Brazilian researchers compared two different studies.

In the first study, a group of resilient older people aged 90 or more were analyzed for long-term symptoms of the disease. The study included 87 resilient cohorts who had recovered from mild CoV-19 or remained asymptomatic after testing positive for SARS-CoV-2. In the second study, a case of severe COVID-19 in identical twins, only one of whom suffered from long-term symptoms of the disease, was analyzed.

Based on the analysis, they found that the frequency of variants of the gene "MUC22" was twice as high in the mild COVID-19 group as it was in severe patients and resilient super-agers. The researchers explained that the "MUC22" gene belongs to the "mucin" family, which is associated with the production of mucus for lubricating and protecting the airways.

They added that in the COVID-infected individual, a mutation in the gene caused the overproduction of mucus, which in turn led to lung inflammation, a typical manifestation of severe infection. The researchers termed this mutation in MUC22 a "missense" variant, where the DNA changes result in different amino acids being encoded at particular positions in the resulting proteins. 

(Source: https://www.daijiworld.com/news/newsDisplay?newsID=1022186 )