To eliminate the variability associated with using samples isolated from different donors, Nam Viet Nguyen (University of California, Irvine) used CRISPR-Cas9 to generate isogenic FSHD models by inducing deletions of D4Z4 repeats or mutations in SMCHD1 starting from the same immortalized muscle cell line from a healthy donor. This evidence concerns the gene SMCHD1 and facioscapulohumeral muscular dystrophy.