Similar to equine IMM, increased skeletal muscle MHC class I expression and perivascular and endomysial lymphocytic infiltrates (CD3+, CD4+, and CD8+) were found in this family with Laing distal myopathy, along with rimmed vacuoles, which are not a feature of equine IMM [6, 48]. The gene discussed is CD4; the disease is distal myopathy.