Significantly more CD4+ and CD8+ microchimeric cells were in the muscle of patients with MD compared with controls (mean 0.053 ± 0.020/mm2 versus 0 ± 0/mm2p = 0.003 and 0.043 ± 0.023/mm2 versus 0 ± 0/mm2p = 0.025, respectively). Here, CD4 is linked to Menkes disease.