Association Between Human Leukocyte Antigen and COVID-19 Severity

In the last days of 2019, a new coronavirus emerged in Wuhan, China, and less than three months its disease, now called COVID-19, was announced a global pandemic by WHO. COVID-19 usually causes respiratory symptoms and can lead to more severe conditions like ARDS. HLA has a crucial role in regulating the immune system; thus, different HLA allele types can be a protective or risk factor for some diseases, so we aimed to find such associations to determine whether some alleles can predict susceptibility or resistibility to COVID-19 and finally facilitate vaccine development. In this case-control study, 15 admitted COVID-19 cases with severe symptoms and ten individuals with mild COVID-19 symptoms were enrolled in the case and control groups, respectively. They were genotyped for HLA A/B/DR loci using a low-resolution HLA typing test. These alleles were more prevalent in case (severe COVID-19) group: A*24 (53.33% vs 10%), B*50 (20% vs 10%), B*55 (20% vs 10%), DRB1*04 (40% vs 20%) and DRB1*11 (53.33% vs 30%) but the difference was only statically significant in A*24 allele (P=0.027; odd ratio=10.286). A*24 was also more prevalent in all patients than the general population in Iran. A*24 was the only allele more prevalent in severe COVID-19 cases with statistical significance. This allele was reported to be a risk factor for such autoimmune diseases as type 1 diabetes, myasthenia gravis, and systemic lupus erythematosus, which may be related to reported immune system hyperresponsiveness in severe COVID-19 cases.