title: Allele-specific RNAi selectively silences mutant SOD1 and achieves significant therapeutic benefit in vivo.
abstract: RNA interference (RNAi) has the potential to treat diseases caused by dominant, gain-of-function type of gene mutations. In these diseases, one allele is mutated and produces a toxic protein, whereas the other allele is normal and performs vital functions. One challenge in the treatment is to specifically inhibit the mutant allele toxicity while maintaining the normal allele function. To test allele-specific silencing in vivo, we made transgenic mice that express an shRNA against mutant Cu, Zn superoxide dismutase gene (SOD1(G93A)), which causes amyotrophic lateral sclerosis (ALS) by a gain of an unknown toxic property. By crossing this transgenic line with mice that express SOD1(G93A) and mice that express wild-type human SOD1, we found that this shRNA specifically silences the mutant, but not the wild-type SOD1. The silencing of the mutant significantly delayed ALS onset and extended survival. Thus, RNAi can achieve allele-specific silencing and therapeutic benefit in vivo.
authors.affiliation: Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 364 Plantation St, 817 LRB, Worcester, MA 01605, USA. xugang.xia@umassmed.edu
authors.forename: Xugang
authors.initials: X
authors.lastname: Xia
authors.forename: Hongxia
authors.initials: H
authors.lastname: Zhou
authors.forename: Yong
authors.initials: Y
authors.lastname: Huang
authors.forename: Zuoshang
authors.initials: Z
authors.lastname: Xu
mesh_terms: D000483:Alleles; D000690:Amyotrophic Lateral Sclerosis / Q000235:genetics / Q000378:metabolism / Q000628:therapy*; D000818:Animals; D002490:Central Nervous System / Q000201:enzymology / Q000473:pathology / Q000503:physiopathology; D004195:Disease Models, Animal; D015536:Down-Regulation / Q000235:genetics; D020868:Gene Silencing / Q000502:physiology*; D015316:Genetic Therapy / Q000379:methods / Q000639:trends; D006801:Humans; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D009046:Motor Neurons / Q000201:enzymology / Q000473:pathology; D009154:Mutation / Q000235:genetics*; D034622:RNA Interference / Q000502:physiology*; D034741:RNA, Small Interfering / Q000235:genetics / Q000627:therapeutic use*; D013482:Superoxide Dismutase / Q000235:genetics* / Q000633:toxicity; D000072105:Superoxide Dismutase-1; D015996:Survival Rate; D016896:Treatment Outcome
chemical_list: D034741:RNA, Small Interfering; C000606290:SOD1 protein, human; C000606291:Sod1 protein, mouse; D013482:Superoxide Dismutase; D000072105:Superoxide Dismutase-1