If you have inherited this rare gene, you are more prone to Alzheimer’s disease and severe Covid-19

London: Researchers have identified an anti-viral gene that has an impact on the risk of Alzheimer’s disease and severe Covid-19.

A team from University College London (UCL) has estimated that a genetic variant of the OAS1 gene increases the risk of Alzheimer’s disease by about 3-6% in the general population, while related variants on the same gene increase the likelihood of serious consequences from Covid-19.

“While Alzheimer’s disease is primarily characterized by a harmful build-up of amyloid proteins and tangles in the brain, there is also significant inflammation in the brain which highlights the importance of the immune system in Alzheimer’s disease. . We have found that some of the same changes in the immune system can occur in both Alzheimer’s disease and Covid-19, ”said lead author Dr Dervis Salih, of the Queen Square Institute of Neurology of the United Kingdom. ‘UCL and the UK Dementia Research Institute.

“In patients with severe Covid-19 infection, there may also be inflammatory changes in the brain. Here, we have identified a gene that may contribute to an exaggerated immune response to increase the risk of Alzheimer’s and of Covid-19, “Salih added, in the article published in the journal Brain.

To understand the link between the gene and Alzheimer’s disease, the team sequenced the genetic data of 2,547 people, half of whom had brain disorders.

They found that people with a particular variation, called rs1131454, in the OAS1 gene were more likely to have Alzheimer’s disease, increasing the baseline risk of people with Alzheimer’s disease by about 11-22%.

The newly identified variant is common and has a greater impact on Alzheimer’s risk than several known risk genes, the researchers said.

In addition, the researchers studied four variants of the OAS1 gene, all of which attenuate its expression (activity).

They found that Alzheimer’s risk-increasing variants are linked (inherited together) with recently discovered OAS1 variants to increase the baseline risk of needing intensive care for Covid-19 by up to 20%.

That is, cells in the microglia where the OAS1 gene was expressed more weakly had an exaggerated response to tissue damage, triggering what they call a “cytokine storm”, which leads to a self-induced state. immune where the body attacks itself, the team said.

OAS1 activity changes with age, so further research on the genetic network could help understand why older people are more vulnerable to Alzheimer’s disease, Covid-19 and others related diseases, they added.