Page URL:

Genetic variant increases Alzheimer's and severe COVID-19 risk

11 October 2021
Appeared in BioNews 1116

A gene variant has been identified that is linked to the development of both Alzheimer's and severe COVID-19, new research has found.

Possessing a variant of the OAS1 gene with a single nucleotide polymorphism was found to lead to significant downregulation of the gene in a type of brain cell (microglia) of both individuals with Alzheimer's and those with severe presentation of COVID-19. The OAS1 gene is associated with an enzyme that breaks down RNA of viral and host cells as part of an immune response to viruses. Carrying this gene variant was linked to as much as a 22 percent increased risk in developing Alzheimer's while also associated with as much as a 20 percent greater probability of needing intensive care for COVID-19.

'Fairly early in the pandemic, people with dementia emerged as a group at particular risk of severe COVID-19 infection. While there are likely to be several reasons for this, the study raises the possibility of a shared genetic risk factor playing a role' said Dr Rosa Sancho, head of research at Alzheimer's Research UK, a researcher not involved in the study.

Over half of Europeans possess this identified gene variant which is linked to the molecular pathways responsible for the release of inflammatory biomarkers, called cytokines, within the brain leading to the damage of neurons. Researchers spearheaded by the UK Dementia Research Institute at University College London (UCL), analysed the genetic sequences of 2547 people, 1313 of whom had Alzheimer's disease and found that many of those with Alzheimer's disease had the implicated gene variant. In addition, single-cell RNA sequencing showed expression of the mouse equivalent of the gene variant increased with age.

This discovery follows on from research conducted by the University of Glasgow, highlighting another OAS1 gene variant that protects carriers by eliciting an earlier immune response after SARS-Cov-2 infection, the virus which leads to COVID-19 (see BioNews 1115). The researchers aim to further these findings by tracking the inflammatory biomarkers in the blood and other bodily fluids around the central nervous system to better assess the damage COVID-19 has on the brain.

'We are also continuing to research what happens once this immune network has been activated in response to an infection like COVID-19, to see whether it leads to any lasting effects or vulnerabilities, or if understanding the brain's immune response to COVID-19, involving the OAS1 gene, may help to explain some of the neurological effects of COVID-19' said Dr Dervis Salih, a lead author and researcher at the UK Dementia Research Institute at UCL.

A genetic link between risk for Alzheimer's disease and severe COVID-19 outcomes via the OAS1 gene
Brain |  7 October 2021
Alzheimer's and COVID-19 share a genetic risk factor
Medical Xpress |  8 October 2021
Gene that increases risk of Alzheimer's 'also raises chance of severe COVID'
The Telegraph |  8 October 2021
Shared genetic risk factor for COVID-19 and Alzheimer’s disease
Alzheimer's Research UK |  8 October 2021
Shared genetic risk factor identified between Covid-19 and Alzheimer’s disease
UK Dementia Research Institute |  8 October 2021
22 November 2021 - by Paige Mumford 
DNA Today is a weekly podcast which aims to 'educate the public on genetic and public health topics.' In this episode on dementia, host Kira Dineen spoke with biochemist Dr Dayan Goodenowe...
4 October 2021 - by Dr Melanie Krause 
Individuals with a specific version of the OAS1 gene have natural antiviral defences against SARS-CoV-2, resulting in less severe COVID-19 disease...
12 July 2021 - by Abbie Harper 
Our genomes can influence the susceptibility and response to SARS-CoV-2 infection, determining the severity of symptoms...
14 June 2021 - by Dr Melanie Krause 
A genetic variant that might provide some protection against severe COVID-19 disease has been identified in a new study led by researchers from Newcastle University...
17 May 2021 - by Elpida Fragouli 
Genomic sequencing has numerous applications, including determining genealogy, the presence or absence of common mutations in a couple who are considering becoming pregnant, and even the susceptibility of contracting SARS-CoV-2, the virus which leads to COVID-19, and the severity of the subsequent disease...
21 December 2020 - by Dr Joanne Delange 
Session three of the Progress Educational Trust (PET) annual conference explored the genetic and genomic links to susceptibility to severe COVID-19...
to add a Comment.

By posting a comment you agree to abide by the BioNews terms and conditions

Syndicate this story - click here to enquire about using this story.