London: A team of scientists led by Newcastle University in the UK has identified the genetic link behind asymptomatic Covid-19 patients, who catch the virus but doesn't become sick.
The study, published in the HLA journal, compared asymptomatic people to patients from the same community who developed severe Covid but had no underlying illnesses.
The team demonstrated that the gene HLA-DRB1*04:01 is found three times as often in these people suggesting that they have some level of protection from severe Covid.
The human leukocyte antigen gene identified as HLA-DRB1*04:01 is directly correlated to latitudes and longitudes. This means, more people in the North and West of Europe are more likely to have this gene.
Now this observation provides answer to why populations of European descent who are more likely to remain asymptomatic still transmit the disease to susceptible populations.
"This is an important finding as it may explain why some people catch Covid but don't get sick," said Carlos Echevarria from the varsity's Translational and Clinical Research Institute."
It could lead us to a genetic test which may indicate who we need to prioritise for future vaccinations."Echevarria added.
The study was carried out using samples from 49 patients with severe Covid who had been hospitalised with respiratory failure, samples from an asymptomatic group of 69 hospital workers who had tested positive through routine blood antibody testing and a control group from a study into the relationship between HLA genotypes and the outcomes of joint replacement surgery.