This Gene Doubles Your Risk of Severe COVID-19, Says Study

Alek Korab

You can wash your hands, self-isolate and practice social distancing—and should!—but scientists are discovering that one other important factor plays a role in the likelihood of you catching a severe case of COVID-19: Your genetics.

A large-scale study has found that a faulty gene linked to dementia doubles the risk of developing severe coronavirus. "Several studies have now shown that people with dementia are at high risk of developing severe COVID-19," said Professor David Melzer, who led the team out of the University of Exeter Medical School and the University of Connecticut School of Medicine. "This study suggests that this high risk may not simply be due to the effects of dementia, advancing age or frailty, or exposure to the virus in care homes."

"It is not just age," he continued, "this is an example of a specific gene variant causing vulnerability in some people."

Trying to Pinpoint Your Vulnerability

How did they discover what they discovered? "Researchers analyzed data from the UK Biobank, and found high risk of severe COVID-19 infection among European ancestry participants who carry two faulty copies of the APOE gene (termed e4e4)," reports the release from Exeter. "One in 36 people of European ancestry have two faulty copies of this gene, and this is known to increase risks of Alzheimer's disease up to 14-fold and also increases risks of heart disease."

"This is an exciting result because we might now be able to pinpoint how this faulty gene causes vulnerability to COVID-19," says co-author Dr. Chia-Ling Kuo, of the UConn School of Medicine. "This could lead to new ideas for treatments. It's also important because it shows again that increasing disease risks that appear inevitable with aging might actually be due to specific biological differences, which could help us understand why some people stay active to age 100 and beyond, while others become disabled and die in their sixties."

Melzer adds: "The effect could be partly due to this underlying genetic change, which puts them at risk for both COVID-19 and dementia."

23andMe Offers Free Genetic Tests to Study Virus

The connection between your genetics and COVID-19 is of peak interest to researchers. 23andMe is offering free genetic tests to 10,000 people who have been hospitalized with the disease. That is happening concurrently with the Covid-19 Host Genetic Initiative, in which university researchers are pairing genetic profiles with medical records from around the world.

"Scientists hope to find a gene that strongly influences, or even determines, how badly people are affected by the coronavirus," reports MIT Technology Review. "There are well-known examples of such genetic effects on other diseases: for example, sickle-cell genes confer resistance to malaria, and variants of other genes are known to protect people from HIV or to norovirus, an intestinal germ."

"If we don't find a really big signal in the next month or so, then I think genetics is not going to be of huge value in the management of the disease, like determining who you treat," Andrea Ganna, who coordinates the Covid-19 Host Genetic Initiative, told the Review. "What is still very, very important is the biology, and understanding the biology through the genetics, and then with vaccination."

As for the new study out of Exeter and UConn: "It is pretty bulletproof—whatever associated disease we remove, the association is still there. So it looks as if it is the gene variant that is doing it … This association is not driven by people who actually have dementia," said Melzer.

As for yourself: To get through this pandemic at your healthiest, don't miss these Things You Should Never Do During the Coronavirus Pandemic.