Meta-analyses of the correlation between PV occurrence and HLA-DRB1 and HLA-DQB1 have shown that DRB1*04, DRB1*08, DRB1*14, DQB1*03:02 and DQB1*05:03 are significant susceptibility factors for PV while DRB1*03, DRB1*07, DRB1*15, DQB1*02, DQB1* 03:03, DQB1*05:01 and DQB1*06:01 were less common in patients with PV compared to healthy individuals (Yan et al., 2012; Li et al., 2018). Here, HLA-DRB1 is linked to acquired polycythemia vera.