(CNN) - Whether a person gets a severe form of COVID-19 could depend on blood type and their DNA, according to a new study conducted by a team of European scientists.
Their findings, published in the New England Journal of Medicine, could help explain why some people get seriously ill with the virus while most barely show any symptoms at all.
The researchers found people with type A blood are at a higher risk of contracting the virus and getting extremely sick from it, while people with type O blood have a lower risk.
The researchers can't say if your blood type is the main reason you may be more or less susceptible to the virus, but they detected genetic variations common in the sickest patients and those could just happen to be linked to a person's blood type.
The variations could be associated with a person's immune response.
An overwhelming overreaction of the immune system is blamed for the deadliest effects of the coronavirus in many patients.
The difference in risk between blood types is small. Researchers say the findings are more useful for designing drugs or vaccines against coronavirus.