HLA-DRB1 and COVID-19: The increased frequencies observed for DRB1*15:01 and DQB1*06:02 in the 99 severe affected COVID-19 Italian patients were not in line with the results obtained in a larger survey [102], which did not show any association between HLA and COVID-19, but confirmed published data [103] identifying these two alleles among seven HLA susceptibility alleles.