Even as countries all over the world ramp up their coronavirus testing capabilities, there’s no way of knowing just how many people have been exposed to SARS-CoV-2. While many individuals develop symptoms and require hospitalization, it appears a significant amount can fend off the infection without incident.
The scientists and doctors of the world are working at a fever pitch to try and form a full understanding of SARS-CoV-2 and how it interacts with our bodies. On that note, one of the biggest questions out there right now is why some people have a much harder time with the coronavirus than others. Now, a new study just released by the American Society for Microbiology is suggesting that genetic variations in people’s immune systems play a big role in explaining these case-by-case discrepancies.
Essentially, the study found that some immune systems are less capable of recognizing the infection. This diminished ability to recognize the coronavirus can make a person more susceptible to developing symptoms in general, as well as more likely to experience severe symptoms that require hospitalization.
Getting down to the scientific specifics of the findings, the study focused on the immune system genes known as human leukocyte antigen genes. These genes are highly involved in the immune system’s ability to recognize pathogens, but they come in a variety of forms and vary from person to person.
“In particular, understanding how variation in HLA [a component of the immune system containing multiple genes] may affect the course of COVID-19 could help identify individuals at higher risk from the disease,” the study reads.
Their study indicates that several immune system gene variations associated with HLAs “likely influence” one’s ability to respond to a SARS-CoV-2 infection. Moreover, it was noted that some alternative HLA gene forms appear to be linked to particularly severe manifestations of the coronavirus in certain patients. A similar conclusion had been drawn in the past regarding severe cases of the original SARS virus that emerged in China back in 2002, so these findings are not completely without precedent.
“This is the first study to report global distributions of HLA types and haplotypes with potential epidemiological ramifications in the setting of the current pandemic,” the study’s authors write.
On a more actionable level, the study’s authors also believe that coronavirus patients can have their HLA genes tested fairly easily. This could be a great way to predict which patients will develop more severe coronavirus symptoms and require extra care.
“HLA typing can be fast and inexpensive,” the study concludes. “Pairing HLA typing with COVID-19 testing where feasible could improve assessment of viral severity in the population. Following the development of a vaccine against SARS-CoV-2, the virus that causes COVID-19, individuals with high-risk HLA types could be prioritized for vaccination.”
From age to exercise habits, it feels like we’re learning more and more on an almost daily basis about why coronavirus affects some people more than others. Our genes influence quite literally everything about us, so it makes sense they have a part to play in all of this as well. Perhaps most importantly, though, HLA testing may help save lives by quickly identifying more at-risk patients.
The full study can be found here, published in the Journal of Virology.