RAG1-SCID HSPCs progress to the DP stage, but with a different immunophenotype than those differentiated from healthy control or RAG1-corrected HSPCs. Flow cytometry of week 8 ATOs. CD7×CD1a (A) and CD3×CD1a (B) flow cytometry plots of CD4/CD8 DP controls and patient cells without and with RAG1 (+LV) correction.