Genetic variation in immune system may affect COVID-19 severity: Study

Genetic variability in the human immune system may affect susceptibility to, and severity of disease due to the novel coronavirus, according to a study which may help identify people at higher risk of the disease.

The research, published in the Journal of Virology, noted that individual genetic variation may explain differences in the strength of immune responses among COVID-19 patients.

According to the researchers, including those from Oregon Health & Science University in the US, certain immune system genes, called human leukocyte antigen genes which are involved in recognising pathogens, vary from person to person.

These variations, they said, can influence how well the immune system recognises a given pathogen.

Poor recognition of the novel coronavirus, SARS-CoV-2, could cause a person to be more vulnerable to the virus, the study noted.

"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 scientists noted in the study.

Based on the study, the scientists said individual HLA and full genotype variability likely influence the capacity to respond to SARS-CoV-2 infection.

They noted that certain sets of genes in particular could be associated with more severe infection, as has previously been shown with SARS-CoV.

"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 researchers wrote in the study.

"Pairing HLA typing with COVID-19 testing where feasible could improve assessment of viral severity in the population," they said.

Following the development of a vaccine against COVID-19, the researchers believe that individuals with high-risk HLA types could be prioritized for vaccination.