Researchers at Oxford University announced their discovery Friday, saying it might explain why some people are more susceptible than others to severe illness from the virus. The discovery may also lead to development of more targeted treatments and medicine to combat the coronavirus.
The research indicates that the lungs’ response to the virus is critical in how the body fights against it.
“The reason this has proved so difficult to work out, is that the previously identified genetic signal affects the ‘dark matter’ of the genome,” explained Jim Hughes, professor of gene regulation and co-lead on the study.
“We found that the increased risk is not because of a difference in gene coding for a protein, but because of a difference in the DNA that makes a switch to turn a gene on,” he said. “It’s much harder to detect the gene which is affected by this kind of indirect switch effect.”
Around 60% of people with South Asian ancestry carry the high-risk variant, the researchers said. The high prevalence might help explain the severe devastation seen in the Indian subcontinent.
Just about 15% of people with European ancestry carry the gene, and only 2% of people of Afro-Caribbean descent.
The team used an artificial intelligence algorithm to comb an immense database of genetic samples from hundreds of types of cells to isolate the action to cells that affect the lungs.
“Surprisingly, as several other genes were suspected, the data showed that a relatively unstudied gene called LZTFL1 causes the effect,” said Dr. Damien Downes, who led the laboratory work from the Hughes research group.
The gene prevents cells lining airways and the lungs from responding properly to the virus, but it does not affect the immune system. This means that people who carry this gene should respond normally to vaccines.
“Although we cannot change our genetics, our results show that the people with the higher-risk gene are likely to particularly benefit from vaccination,” said another researcher, James Davis. “Since the genetic signal affects the lung rather than the immune system it means that the increased risk should be cancelled out by the vaccine.”