Despite there being very little data about class I and II HLA alleles correlated to decreased risk to development of COVID-19, a study has shown that the alleles HLA-A*02:01 and HLA-A*03:01, only when express in homozygosity, are not correlated to severe COVID-19 development [23]; HLA-A*68:02 was correlated to decreased risk to ICU admission in hospitalized COVID-19 patients and in addition, HLA-B*14 was correlated to decreased mortality in COVID-19 patients [27], however, the molecular mechanism is still not fully clear. This evidence concerns the gene HLA-B and COVID-19.