Using CRISPR/Cas9 System to Knock out Exon 48 in DMD Gene

Background: out of frame mutations in dmd gene cause duchenne muscular dystrophy(dmd) which is a neuromuscular progressive genetic disorder. in dmd patients, lack ofdystrophin causes progressive muscle degeneration, which results in heart and respiratoryfailure leading to premature death. at present, there is no certain treatment for dmd.dmd gene is the largest gene in human genome by 2.2 mega base pairs and contains 79exons. in the past few years, gene therapy has been considered a promising dmd treatment,and among various gene-editing technologies, crispr/cas9 system is shown to bemore precise and reliable. the aim of this study was to assess the possibility of knockingout exon 48 by using a pair of sgrnas.methods: a pair of guide rnas (grnas) was designed to cleave dmd gene and inducedeletion of exon 48. grnas were transfected to the hek-293 cell line and then the deletionin genomic dna was analyzed by pcr and subsequent sanger sequencing.results: exon 48 was successfully deleted and therefore exon 47 was joined to exon 49.conclusion: this result indicated that crispr/cas9 system could be used to edit dmdgene precisely.