BCL11A and Schnyder corneal dystrophy: CTX001 reduces BCL11A expression in erythrocytes, restores γ‐globin synthesis, and produces high levels of HbF in erythrocytes by gene editing patients’ HSCs in vitro with CRISPR–Cas9, thereby re‐infusing the gene‐edited HSCs into patients to stimulate the synthesis of HbF in the patients, to restore the normal functioning of their RBCs for the treatment of severe SCD and β‐thalassemia.