In the present study, we demonstrate the following: (1) fewer early EPC colonies were produced in patients with CAD than in control subjects and higher late EPC colonies were found in patients with CAD similarly; (2) in early EPCs, levels of CD45 mRNA, which is a hematopoietic marker, were higher in CAD patients than in control subjects; (3) in late EPCs, the level of CD31 mRNA, which is an endothelial marker, was lower in CAD patients than in control subjects. The gene discussed is PTPRC; the disease is coronary artery disorder.