Research led by St. Jude Children’s Research Hospital and Harvard University shows base-editing approaches could be more effective than CRISPR-Cas9 gene-editing approaches for treating conditions such as sickle cell disease and β-thalassemia. Writing in the July 3, 2023, issue of Nature Genetics, the researchers compared three base-editing approaches with two CRISPR-Cas9 approaches to increasing levels of fetal hemoglobin in CD34+ hematopoietic stem and progenitor cells, and found one of the base-editing approaches was the most potent.