In April, not long after the pandemic began, the genetic testing firm 23andMe began using its testing services to help scientists better understand how genetics may play a role in why some people who contract the novel coronavirus, SARS-CoV-2, develop severe infections, while others present only mild or moderate symptoms or have no symptoms at all.
On Monday, the company released early results from the study, which involved more than 750,000 participants.
“Preliminary data from 23andMe’s ongoing genetic study of COVID-19 appears to lend more evidence for the importance of a person’s blood type — determined by the ABO gene — in differences in the susceptibility to the virus,” the company said in a blog post regarding the findings.
More specifically, type O blood may be protective against the novel virus. In fact, early results indicate that people with type O blood are between 9 and 18 percent less likely to test positive for COVID-19 when compared to the other blood types.
“These findings hold when adjusted for age, sex, body mass index, ethnicity, and co-morbidities,” the company noted, adding that there “appeared to be little differences in susceptibility among the other blood types.”
“There have also been some reports of links between COVID-19, blood clotting, and cardiovascular disease,” Adam Auton, the study’s lead researcher, told Bloomberg. “These reports provided some hints about which genes might be relevant.”
That said, “It’s early days; even with these sample sizes, it might not be enough to find genetic associations,” he added. “We’re not the only group looking at this, and ultimately the scientific community may need to pool their resources to really address questions surrounding the links between genetics and COVID-19.”
Still, the study’s early results are in line with other studies that have looked into how a person’s blood type may play a role in virus susceptibility.
For instance, a study out of China that was published in March also found that those with type O blood may be more resistant to SARS-CoV-2, while those with type A blood might be more at risk.