People who have a particular genetic variant are twice as likely to never get sick when they contract COVID-19, researchers said on Wednesday, offering the first potential explanation for the lucky group dubbed the "superdodgers."

Those who have two copies of the variant are eight times more likely to never get any symptoms from COVID-19, according to the study in the journal Nature.

Previous research has suggested that at least 20% of the millions of COVID-19 infections during the pandemic were asymptomatic.