HLA-B and COVID-19: The allele frequency of HLA-A-Bw4 was reduced in the deceased Russian COVID-19 patients compared to their controls (18.5% vs. 22.1%); although the overall frequency of HLA-Bw4 allotypes was similar in patients and controls, HLA-B-Bw4-80 T alleles were reduced in the deceased patients (16.7%) compared to controls (21.3%), while HLA-B-Bw4-80I was increased in COVID-19 (23.4%) than controls (19.3%) (Figure 6A).