A human autopsy cohort of pathologically confirmed MS cases (n = 41) from both HLA‐DRB1*15‐positive (n = 18) and HLA‐DRB1*15‐negative subgroups (n = 23), and non‐neurological control cases (n = 7) was obtained from the UK MS Tissue Bank in compliance with Human Tissue Act guidelines (REC 08/MRE09/31 + 5). Here, HLA-DRB1 is linked to myeloid sarcoma.