DMPK and myotonic dystrophy type 1: To confirm that these DM1-associated phenotypes were caused by CTGexp of the DMPK gene, we generated isogenic control for DM1-hiPSCs from Pt-1 by the CRISPR-Cas9 method utilizing two sgRNAs to cut out the 5'-side and 3'-side of the CTG repeats31.