EWSR1 and Ewing sarcoma: et al. developed a novel method that combines CRISPR/Cas9 with HDR to engineer and modulate the expression of chromosomal translocation products, and allowed the expression of the EWSR1-FLI1 fusion gene to be controlled in a timely manner, which effectively solved the problem that the permanent generation of the EWSR1-FLI1 fusion gene caused the expression change of its intracellular target gene in a short time and made them difficult to precisely target, This strategy is undoubtedly more conducive to the study of the genetic and pathogenic mechanisms of ES [71].