A study of more than 45,000 people gives a clue as to why some people get sick after an infection.
Some people may blame their DNA for making them more likely to get COVID-19 or severe illness if they are infected.
A study of more than 45,000 people with COVID-19 found 13 genetic variants associated with an increased risk of SARS-CoV-2 infection or a higher likelihood of developing severe disease, researchers report July 8 in the journal Nature. The group includes more than 3,300 researchers from 25 countries.
Some of the variants have been found in previous studies. For example, the researchers reiterated the genetic link between blood type and likelihood of infection, but don’t know why people with blood type O might be somewhat protected. The study also confirmed that a variant that turns off the TYK2 gene increases the risk of critical illness and hospitalization. This variant is known to protect against autoimmune diseases, but makes people more vulnerable to tuberculosis.
But at least one association was unknown: A variant in a gene called FOXP4 is associated with a more severe course of COVID-19, the team found. This variant increases gene activity and has previously been linked to lung cancer and interstitial lung disease, a group of diseases that cause scarring and lung stiffness. Drugs that have not yet been developed that inhibit the activity of the FOXP4 protein could help people recover from COVID-19 or prevent the disease from developing.
The version of the gene linked to the disease is more common among Asians and Hispanics, geneticist Mark Daly said at a July 7 briefing. The link might never have been discovered had the study not included people with different backgrounds from around the world, said Daly, of the Finnish Institute of Molecular Medicine in Helsinki (SN: 3/4/21). Only 2 to 3 percent of people with European ancestry have the variant, compared with 7 percent of people from the Middle East, 20 percent of Hispanics and 32 percent of East Asians.