Scientists are working hard to figure out the mysteries of COVID-19, including whether or not some people who have never had it are immune. But experts currently disagree on whether these so-called "superdodgers" exist. Some scientists speculate that some of the folks who haven't yet had COVID-19 actually have had it but just didn't know it, because they were totally asymptomatic. Along this line of thinking, researchers at UC San Francisco have found that some people have a genetic mutation that prevents them from having COVID-19 symptoms even if the virus infects their cells. In other words, this mutation doesn't stop infection, but it does stop any symptoms from developing.
Other scientists like Jean-Laurent Casanova and his team at Rockefeller University are conducting research to find out if there are actually people who never are infected to begin with, even if they are exposed to COVID-19—folks who have "true superdodger genes." LAist explains that while not impossible, this would be pretty rare:
Over the course of human history, scientists have identified only two instances of true virus superdodgers. That is, where a specific mutation in their genes makes people completely resistant to a virus. So that it slides off their cells, "like water sliding off a glass window," as Casanova puts it.
In order to find out, Casanova and his team are currently recruiting participants. LAist explains:
"You fill out a questionnaire online about your exposures to SARS-CoV-2," he says. And then if you meet the criteria of a superdodger, the team sends you a testing kit. Basically you spit in a cup and mail it back to Casanova and his collaborators.
On their research website, they explain the purpose of the study:
Why do some people get very ill from Coronavirus infection (COVID-19), others experience little or no symptoms, while yet others do not get infected at all? Rather than luck, we think the answer is in our genome and immunity. Our genes are small, yet mighty and can control our immunity in even the most subtle ways. This may explain why some people seem better equipped than others to fight this new virus. Immunity can also be disrupted by non-genetic mechanisms, which can be found thanks to the 'genetic compass'.
Our mission is to find out why and how our genes affect our immunity against Coronavirus, and how and why immunity can also be affected by other, non-genetic causes. This discovery will allow us to develop new ways to combat this pandemic: through better and faster diagnosis, new drugs for the treatment and prevention of infection, new ways to develop a vaccine, and a better understanding of how this infection works in the body.