Paroxysmal nocturnal hemoglobinuria: Significant association with specific HLA-A, -B, -C, and -DR alleles in an Italian population

Summary Paroxysmal nocturnal hemoglobinuria (PNH) is characterized by the expansion of a PIG-A mutated hematopoietic stem cell. An immune-mediated origin has been suggested for this disease. Because HLA genes represent a susceptibility factor for autoimmunity, we investigated HLA genotype in 42 Italian PNH patients compared with 301 control subjects of the same ethnic origin. A significantly increased frequency of the HLA class I alleles A*0201 ( p p p p p ≤ 0.05) and DRB1*01 ( p ≤ 0.05) with the linked DQB1*0501 ( p ≤ 0.01) alleles, has been observed. Notably, a fourfold increase of the haplotype B*1402, Cw*0802 ( p p