COVID-19 has had a significant impact on millions of people globally, resulting in hospitalization, extended bed rest, and loss of life. However, there is a group of individuals who have contracted the virus but have not experienced any symptoms. Researchers believe that this phenomenon could be explained by the human leukocyte antigen (HLA), which aids the immune system in early infections.
A mutated HLA gene, specifically HLA-B*15:01, may be the reason why some people do not develop symptoms even after being infected with the SARS-CoV-2 virus that causes COVID-19. A recent study published in Nature found that individuals with the mutated gene were more than twice as likely to remain asymptomatic. Those with two copies of the gene were over eight times more likely to show no symptoms.
While the gene variant does not prevent the virus from entering the body, it does prevent the development of symptoms like runny nose, fever, and sore throat. Researchers identified this link by studying a database of bone-marrow donors and enrolling nearly 30,000 people who self-reported positive tests for SARS-CoV-2. Of the participants, 136 remained asymptomatic.
The mutated HLA gene allows T-cells to recognize COVID-19 even without previous exposure to the virus. This may be due to exposure to other similar coronaviruses, such as those causing the common cold. The gene functions like exceptional facial recognition skills, providing T-cells with increased adaptability and effectiveness in recognizing pathogens.
It’s important to note that asymptomatic individuals can still transmit the virus to others, despite not experiencing any symptoms themselves. This presents a risk to those around them. Understanding the genetic factors involved in combating COVID-19 could lead to improved diagnostic tests and therapeutic advancements in the future.