技术资料

Huntington’s disease (HD) is the best-known example of a neurodegenerative disorder caused by the expansion of a glutamine-encoding CAG repeat in the causative gene. Growing evidence indicates that somatic CAG expansions play a key role in disease progression,providing a strong rationale for therapeutic strategies directly targeting the repeat tract. However,achieving sufficient efficacy while maintaining allele selectivity and minimizing off-target effects remains a major challenge. Here,we developed allele-selective,CAG-targeting artificial microRNA (amiRNA) molecules that exhibit significantly reduced off-target risk. This was achieved by introducing specific substitutions at selected positions within the guide strand. These molecules effectively downregulated polyglutamine (polyQ) proteins in cellular models of HD,spinocerebellar ataxias types 1 and 3,and dentatorubral pallidoluysian atrophy. The most promising candidate,amiR136-13A,reduced mutant huntingtin levels in different brain regions of the HD mouse model and did not induce toxicity up to 28 weeks following a single administration of an AAV5 vector. Transcriptomic profiling of human HD neural stem cells treated with amiR136-13A revealed minor changes in gene expression. Moreover,amiR136-13A reduced the level of HTT1a,a short pathogenic isoform of huntingtin. Collectively,these findings identify amiR136-13A as a potent,selective,and safe therapeutic candidate for HD and potentially other polyQ disorders. View Publication