biostudies-literaturePini VMedical Research CouncilNational Institute for Health Research (NIHR)Muscular Dystrophy UK3756https://www.ebi.ac.uk/biostudies/studies/S-EPMC8904532biostudies-literatureUnknown12(1)Among the mutations arising in the DMD gene and causing Duchenne Muscular Dystrophy (DMD), 10-15% are multi-exon duplications. There are no current therapeutic approaches with the ability to excise large multi-exon duplications, leaving this patient cohort without mutation-specific treatment. Using CRISPR/Cas9 could provide a valid alternative to achieve targeted excision of genomic duplications of any size. Here we show that the expression of a single CRISPR/Cas9 nuclease targeting a genomic region within a DMD duplication can restore the production of wild-type dystrophin in vitro. We assessed the extent of dystrophin repair following both constitutive and transient nuclease expression by either transducing DMD patient-derived myoblasts with integrating lentiviral vectors or electroporatScientific reportsTransiently expressed CRISPR/Cas9 induces wild-type dystrophin in vitro in DMD patient myoblasts carrying duplications.PMC8904532RA3/3076Farmer SConti FPini VDumonceaux JO'Neill HCCounsell JMuntoni FMariot VfalseTransiently expressed CRISPR/Cas9 induces wild-type dystrophin in vitro in DMD patient myoblasts carrying duplications.Among the mutations arising in the DMD gene and causing Duchenne Muscular Dystrophy (DMD), 10-15% are multi-exon duplications. There are no current therapeutic approaches with the ability to excise large multi-exon duplications, leaving this patient cohort without mutation-specific treatment. Using CRISPR/Cas9 could provide a valid alternative to achieve targeted excision of genomic duplications of any size. Here we show that the expression of a single CRISPR/Cas9 nuclease targeting a genomic region within a DMD duplication can restore the production of wild-type dystrophin in vitro. We assessed the extent of dystrophin repair following both constitutive and transient nuclease expression by either transducing DMD patient-derived myoblasts with integrating lentiviral vectors or electroporat2022-01-01T00:00:00Z2022 Mar2025-04-04T08:24:22.872Z2025-04-04T08:24:22.872ZS-EPMC89045323526065110.1038/s41598-022-07671-w