HOXA5 expression in CD34⁺ cells decreases the frequency of erythroid progenitors (BFU-E). CD34⁺tNGFR⁺ cells were isolated after transduction and immediately plated in semisolid medium to enumerate and characterize CFU-C content. Shown are data from seven independent experiments. *P < .016. (▪) HOX A5; (▨) control.