A recent FDA-approved CRISPR-Cas9 gene therapy offers new options in treating sickle cell disease (SCD) . SCD is characterized by sickling of red blood cells (RBCs). Although the mutation occurs within the adult beta hemoglobin gene, researchers found that fetal hemoglobin (HbF) rescues the defective beta hemoglobin by hindering the sickling process. Using CRISPR-Cas9 technology to target the erythroid lineage specific enhancer region of BCL11A induces the production of HbF, which inhibits sickling. Read more about the science behind the breakthrough CRISPR-Cas9 gene therapy to treat SCD.