There are a few studies that show a higher frequency of HLA-DRB1*11 and/or HLA-DQB1*03 in patients with hematologic malignancies [83], non-Hodgkin’s lymphoma, diffuse large B-cell lymphoma [84], mycosis fungoides (cutaneous T-cell non-Hodgkin’s lymphoma) [85–88], acute lymphoblastic leukemia [89], chronic lymphocytic leukemia [90], hairy cell leukemia (B-cell leukemia) [91], and HCV virus-associated lymphoma [92] compared to controls. This evidence concerns the gene HLA-DRB1 and hairy cell leukemia.