Scientists Use Base Editing to Reduce Harmful DNA Repeat Expansions in Huntington's and Friedreich's Ataxia Cells and Mice

Base editing of trinucleotide repeats that cause Huntington’s disease and Friedreich’s ataxia reduces somatic repeat expansions in patient cells and in mice

MainTrinucleotide repeat (TNR) sequences are common genomic elements that can become unstable in a length-dependent manner. Pathogenic expansion of TNRs is associated with over 40 severe, predominantly neurological disorders1. TNRs may be localized to gene promoters, coding sequences, untranslated regions and introns, and the repeat motif can vary between TNR disorders2. The most common pathogenic triplet base pair is CAG•CTG, which occurs in at least 15 known pathogenic TNR loci2. CAG repeats i...