HLA-DRB1 and myeloid sarcoma: The frequency of CCSVI negative- HLA DRB1*1501 negative status in Controls was more than two-fold greater than in MS patients (54.8% in Controls vs. 23.9% in MS), whereas the frequency of CCSVI positive- HLA DRB1*1501 positive status in MS patients (8.4% in Controls vs. 31.7% in MS) was more than three-fold greater than in Controls.