Gene discovered that provides protection from COVID-19
Print Science Editor Ellen Rogers discusses the potential impact of recent research showing a genetic correlation with the severity of people’s COVID symptoms.
Throughout the COVID-19 pandemic, the impact of COVID disease on individuals and entire separate populations has varied greatly. Some individuals seem not to manifest disease symptoms (known as asymptomatic carriers), whilst others are hospitalised with severe pulmonary and respiratory disease. Susceptibility to severe COVID-19 disease has been seen in people from certain ethnic minority groups, with a disproportionately large number of hospitalised cases originating from individuals of these backgrounds, but it was not understood why this was. Now, new research by a team of scientists and medical professionals at Newcastle University may explain these observations, revealing the first genetic link that explains why some individuals remain asymptomatic when exposed to the novel coronavirus.
The team’s research was focused on the HLA-DRB1*04:01 gene, which is located on chromosome 6 and encodes proteins important for the function of our immune system. Specifically, the HLA-DRB1 gene is part of the human leukocyte antigen (HLA) complex, which helps the body to identify disease-causing invading microorganisms, such as the coronavirus. By comparing the genetic makeup of people severely affected by COVID-19 to asymptomatic patients, the team demonstrated that the HLA-DRB1*04:01 gene is three times as common in asymptomatic individuals. This suggests that this gene conveys some protection against COVID.
The HLA-DRB1*04:01 gene is three times as common in asymptomatic individuals
This research is known as a genome-wide association study (GWAS), which aims to identify linkages between genetic variants and physical characteristics expressed by an individual. Compared to other GWAS, which consider all an individual’s genetic material, the Newcastle team’s research focused on the HLA gene cluster on chromosome 6, and thus was able to reveal the protective role of the HLA-DRB1*04:01 gene against COVID. It is already known that the frequency of the HLA-DRB1*04:01 gene is directly correlated to latitude and longitude – meaning that European populations, specifically those in Northern and Western Europe, are likely to have higher numbers of asymptomatic carriers within them. It is estimated that approximately one in five people of European descent in the UK carry this gene.
HLA-DRB1*04:01 gene is directly correlated to latitude and longitude – meaning that European populations, specifically those in Northern and Western Europe, are likely to have higher numbers of asymptomatic carriers within them.
On a population level (both in the UK and globally), testing for this gene could help keep rates of infection low as restrictions are relaxed. A genetic test would enable us to identify individuals who are more likely to be asymptomatic carriers and transmitters of COVID and prioritise them for vaccination. Highlighting and summarising the importance of increased research into the novel coronavirus, Professor Sir John Burn, the co-author of this research, said: “the more we understand why some people become sick, the better we can defend ourselves against this virus and others like it in future”