Interestingly, in TAO patients the proportion of CD45dimCD34+VEGFR2+ progenitor cells was remarkably elevated compared to both smokers (4.7±1.0% vs. 2.1±0.6%, P = 0.035) and nonsmokers (4.7±1.0% vs. 1.5±0.2%, P = 0.008) (Figure 1D). This evidence concerns the gene KDR and thromboangiitis obliterans.