First, MEPs which represent 9.6 ± 1.8% of the CD34+ cells in the healthy controls, were significantly lower in SCD patients with averages of 5.2 ± 0.1% and 5.4 ± 0.1% in the transfusion and naive groups, respectively, and only 2.6 ± 0.4% in the HU group. Here, CD34 is linked to Schnyder corneal dystrophy.