Since the creation of the CRISPR/Cas9 gene-editing tool, many new opportunities have opened up for the treatment of diseases that are rooted in deleterious genetic mutations. The technique comes from a system that bacteria use for immunity protection, and it has been adapted to target specific places in the genomes of a variety of organisms, including humans. However, there are serious limitations to the standard technique, and many scientists are looking for safer ways to control gene expression in human patients.
You can learn more about how scientists have now altered the CRISPR/Cas9 system so that epigenetic changes can be applied instead of the more permanent ones typically made. Epigenetic modifications, in which chemical tags might be added, or removed, are considered to be far less risky, but they still change gene expression in a way that may treat disease. There were challenges in the invention of this tool; learn more about them, and the results of the work, from the video.