In HLA‐DRB1*15− MS cases microglia positively correlated with neurons, a finding not observed in HLA‐DRB1*15+ MS cases, after correction for fibrinogen deposition, age, sex, and post‐mortem interval (HLA‐DRB1*15− MS cases: Iba1+: β = 0.549, p = 0.005; CD68+: β = 0.544, p = 0.004; TMEM119+: β = 0.438, p = 0.036; HLA‐DRB1*15+ MS cases: Iba1+: β = −0.266, p = 0.422; CD68+: β = −0.178, p = 0.582; TMEM119+: β = 0.168, p = 0.513). The gene discussed is AIF1; the disease is myeloid sarcoma.