Researchers test CRISPR/XIST approach to turn off extra chromosome in Down syndrome cells

A study from Beth Israel Deaconess Medical Center and Harvard uses a modified CRISPR/Cas9 to insert the chromosome-silencing XIST RNA into trisomy 21 cells, silencing the extra chromosome in a subset of cell lines and offering a potential path toward chromosomal therapy for Down syndrome, but much work remains to assess safety, delivery, and whether effects translate to animals and humans.