About Duchenne Treatments In The Pipeline CRISPR Gene editing (CRISPR/Cas9) CRISPR /Cas 9 is an exciting genetic engineering technique. It has two key components: Cas9 which is an enzyme that can cut DNA at a precise point CRISPR, a short strand of RNA, a chemical messenger Three research groups, working independently of one another, recently reported in the journal Science that they had used the Crispr-Cas9 technique to treat mice with a defective dystrophin gene. Each group loaded the DNA-cutting system onto a virus that infected the mice’s muscle cells, and ‘cut out’ an exon from the gene. Without the defective exon, the muscle cells made a shortened but functional dystrophin protein, giving all of the mice more strength. There are high hopes for the application of the CRISPR Cas9 technology for Duchenne however, for now, the state of the science and the corporate interest is classified as early stage. We at Duchenne UK have funded the work of Dr Ronald Cohn, Chief of Clinical and Metabolic Genetics and Co-director of the Centre for Genetic Medicine at SickKids in Canada, who has used CRISPR to remove a duplicated gene and restore protein function in cells from a child with Duchenne muscular dystrophy. We are also co-funding a £180,000 three-year gene editing project by Professor Francesco Muntoni, of University College London. His work, like Ronald Cohn’s, aims to remove an extra copy of the dystrophin gene, which causes Duchenne in around 15% of cases.