Impaired erythropoiesis in MT iPSCs. (A) Colony formation assay on day 14 of hematopoietic differentiation. Each line was tested in 3 independent experiments. (B) Erythroid and mixed colony counts in panel A. (C) Representative images of erythroid (left) and mixed (right) colonies derived from WT1-iPSC2. Magnification of the objective lens: ×4. Bars represent 200 μm. (D) Erythroid and mixed colony counts in MT HPCs transduced with WT ALAS2. Each line was tested in 3 independent experiments. (E) Percentages of CD43⁺ hematopoietic cells. Each line was tested in 3 independent experiments. (F) Percentages of CD235a⁺ erythroblasts. Each line was tested in 3 independent experiments. All data are presented as the mean ± standard error of the mean. P-values were calculated by using the unpaired, 2-tailed Student t test. ****P < .0001; N.S., not significant.