HLA-A and COVID-19: Connection of HLA-A*01:01 and HLA-A*02:01 alleles with COVID-19 morbidity and mortality was already mentioned in the existing literature, namely, frequency of HLA-A*01:01 in Italian regions positively correlated both with the number of COVID-19 cases and deaths, while significant negative correlation was observed for HLA-A*02:01 (13).