Blood group plays an important in one’s susceptibility to coronavirus. Researchers say that while people with blood group A are at a high risk of developing COVID-19, O blood group has less chance.
Blood Groups at High and Low Risks of COVID-19
The latest research conducted by genetic-testing giant 23andMe revealed that people with O blood groups are protective against the coronavirus. Both (O-negative and O-positive) are at a lower risk of developing an infection as compared to other blood groups. People with blood group O are 9 to 18% less likely to test positive for COVID-19 as compared to other blood groups. The results were derived after testing around 750,000 participants. Further, findings suggest that individuals with blood group A are at a higher risk of needing oxygen support from severe complications of the coronavirus.
The researchers became curious about the genetic factor when they found that some people contracted the virus and others didn’t. Though factors like age and underlying health conditions determine the way an individual responds to the infection, these factors do not explain the diversity of symptoms.
Other Studies
Several other studies have emphasized the role of blood type is affecting the severity of illness and susceptibility to disease. A study in China revealed that blood type A (A-positive, A-negative, and AB-positive, AB-negative) is at a higher risk for acquiring COVID-19. On the other side, those with O blood group showed more protection against the infection. Researches conducted in Italy and Spain revealed a similar result. Moreover, out of 1,600 patients experiencing respiratory failure were of blood group A. Also, 50% of them were likely to require a ventilator.
Likewise, in America, scientists tested 1,559 people for SARS-CoV-2 at New York-Presbyterian Hospital. Out of these, 682 tested positive. The results revealed that the A(positive or negative) was 33% more likely to test positive as against the non-A ones. The conclusive results are based on the theory of antigen. The blood type determines the production of the kind of antigens that cover the surfaces of their blood cells. That, in turn, affects the production of antibodies to help fight off a pathogen.
Genome Research on the Link Between Coronavirus and blood Group
Genome-wide association (GWAS) study, published in the New England Journal of Medicine found that gene variants in two sections of the human genome are associated with COVID-19. Another study revealed that blood groups impact the set of proteins produced by cells. Also, it noted that this area includes a genetic variant associated with increased levels of interleukin-6, which plays a role in inflammation and the implications of COVID-19.
To back the research, the researchers compared single-nucleotide polymorphisms or SNPs of people with severe COVID-19 with healthy blood donations. They found out two places that turned up more in severely infectious people. One being chromosome 3, which covers a cluster of six genes encoding a transporter protein that interacts with the surface receptor that allows the novel coronavirus to bind with human cells. The other association of signal popped up on chromosome 9 over the area of the genome that determines blood type. The studies found evidence of the link between blood type and coronavirus.
In all, the results are compelling but not conclusive. The reason for the blood group increasing or decreasing a person’s risk of getting SARS-CoV-2 requires more research.