Identification and allele-specific silencing of the mutant huntingtin allele in Huntington's disease patient-derived fibroblasts.
Huntington's disease (HD) is a dominantly inherited neurodegenerative disorder caused by the expression of mutant huntingtin protein (Htt). Suppression of Htt expression, using RNA interference, might be an effective therapy. However, if reduction of wild-type protein is not well tolerated in the brain, it may be necessary to suppress just the product of the mutant allele. We present a small interfering RNA (siRNA) that selectively reduces the endogenous mRNA for a heterozygous HD donor's pathogenic allele by approximately 80% by specifically targeting a single-nucleotide polymorphism (SNP) located several thousand bases downstream from the disease-causing mutation. In addition, we show selective suppression of endogenous mutant Htt protein, using this siRNA. We further present a method, using just a heterozygous patient's own mRNA, to determine which SNP variants correspond to the mutant allele. The method may be useful in any disorder in which a targeted SNP is far downstream from the pathogenic mutation. These results indicate that allele-specific treatment for Huntington's disease may be clinically feasible and practical.
Medtronic Bakken Research Center, Corporate Science and Technology, 6229 GW Maastricht, The Netherlands.
P H J
PH
van Bilsen
L
L
Jaspers
M S
MS
Lombardi
J C E
JC
Odekerken
E N
EN
Burright
W F
WF
Kaemmerer
D000328:Adult; D000483:Alleles; D002478:Cells, Cultured; D017931:DNA Primers; D005260:Female; D005347:Fibroblasts / Q000378:metabolism; D015316:Genetic Therapy / Q000379:methods*; D006801:Humans; D000071058:Huntingtin Protein; D006816:Huntington Disease / Q000235:genetics / Q000628:therapy; D008875:Middle Aged; D050505:Mutant Proteins / Q000235:genetics* / Q000378:metabolism; D009154:Mutation; D009419:Nerve Tissue Proteins / Q000235:genetics* / Q000378:metabolism; D009687:Nuclear Proteins / Q000235:genetics* / Q000378:metabolism; D016133:Polymerase Chain Reaction; D020641:Polymorphism, Single Nucleotide; D034622:RNA Interference; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism
D017931:DNA Primers; C086055:HTT protein, human; D000071058:Huntingtin Protein; D050505:Mutant Proteins; D009419:Nerve Tissue Proteins; D009687:Nuclear Proteins; D012333:RNA, Messenger; D034741:RNA, Small Interfering