Blood Group type may decide susceptibility to Covid 19 respiratory failure

Respiratory failure is a major symptom that leads to Covid death

Oslo: The dangerous symptom of Covid infection that may lead to death is respiratory malfunction. This results as the viral infection spreads to the lungs. Researchers have identified two human gene variants that could make people more susceptible to lung failure associated with Covid-19.

Tom Karlsen at Oslo University Hospital and his colleagues analysed the genomes of roughly 4,000 people from Italy and Spain. Among them, they collected samples from 1,980 people having Covid 19 respiratory failure and some 2000 samples of people who were not affected.  Those with severe Covid-19 were more likely to carry either of two gene variants than people without the disease.

One variant lies in the swathe of the genome that determines blood groups. Careful study led to the conclusion that people with blood group A+ showed lung failure more compared with those with the other blood types. Specifically, infected people with blood group O were protected to some extent. The study flagged a second variant, on chromosome 3, that is near six genes, including one that interacts with the molecular receptor the virus uses to enter human cells. Anyway, this study is not peer-reviewed. 

The variations in symptoms have often defied age and gender trends that largely suggest older men may be more vulnerable to the virus. There have been a significant number of young people who have succumbed to the illness. The researchers noted that their findings corroborate publicly available results from the Covid-19 Host Genetics Consortium, where similar associations have been noticed among Covid-19 affected cases versus a population-based sample. The findings in connection with the blood groups also associate with another Covid-19 symptom seen among people who develop serious illness: blood clotting. “Genetic variation at the ABO locus has previously been associated with a number of pro-coagulant markers such as von Willebrand factor and Factor VIII, and the potential relationship between our genetic findings and the significant coagulopathy that is observed in severe Covid-19 warrants further attention,” the researchers wrote.

Genome-wide association studies are among the key strategies, researchers deploy to understand a disease. The genome, simply put, determines how a human body is made up at a cellular level and the functions it carries out, whether to make or repair new cells. Researchers hope these studies to be extremely helpful now, as treatment to this pandemic is still in its childhood. “There is usually a strong relationship between blood group and disease. But it is very difficult at this stage to determine this particular correlation unless there is a very huge study,” said Dr RN Makroo, a specialist in molecular biology. “The distribution of blood groups in population also needs to be accounted for,” he added.