A majority of Huntington's disease patients may be treatable by individualized allele-specific RNA interference

Maria Stella Lombardi, Leonie Jaspers, Christine Spronkmans, Cinzia Gellera, Franco Taroni, Emilio Di Maria, Stefano Di Donato, William F. Kaemmerer

Research output: Contribution to journalArticle

Abstract

Use of RNA interference to reduce huntingtin protein (htt) expression in affected brain regions may provide an effective treatment for Huntington disease (HD), but it remains uncertain whether suppression of both wild-type and mutant alleles in a heterozygous patient will provide more benefit than harm. Previous research has shown suppression of just the mutant allele is achievable using siRNA targeted to regions of HD mRNA containing single nucleotide polymorphisms (SNPs). To determine whether more than a minority of patients may be eligible for an allele-specific therapy, we genotyped DNA from 327 unrelated European Caucasian HD patients at 26 SNP sites in the HD gene. Over 86% of the patients were found to be heterozygous for at least one SNP among those tested. Because the sites are genetically linked, one cannot use the heterozygosity rates of the individual SNPs to predict how many sites (and corresponding allele-specific siRNA) would be needed to provide at least one treatment possibility for this percentage of patients. By computing all combinations, we found that a repertoire of allele-specific siRNA corresponding to seven sites can provide at least one allele-specific siRNA treatment option for 85.6% of our sample. Moreover, we provide evidence that allele-specific siRNA targeting these sites are readily identifiable using a high throughput screening method, and that allele-specific siRNA identified using this method indeed show selective suppression of endogenous mutant htt protein in fibroblast cells from HD patients. Therefore, allele-specific siRNA are not so rare as to be impractical to find and use therapeutically.

Original languageEnglish
Pages (from-to)312-319
Number of pages8
JournalExperimental Neurology
Volume217
Issue number2
DOIs
Publication statusPublished - Jun 2009

Fingerprint

Huntington Disease
RNA Interference
Alleles
Small Interfering RNA
Single Nucleotide Polymorphism
High-Throughput Screening Assays
Mutant Proteins
Genetic Therapy
Therapeutics
Fibroblasts
Messenger RNA
Brain

Keywords

  • Allele-specific
  • Haplotype
  • Huntington's disease
  • Pyrosequencing
  • RNA interference
  • Small interfering RNA

ASJC Scopus subject areas

  • Neurology
  • Developmental Neuroscience

Cite this

A majority of Huntington's disease patients may be treatable by individualized allele-specific RNA interference. / Lombardi, Maria Stella; Jaspers, Leonie; Spronkmans, Christine; Gellera, Cinzia; Taroni, Franco; Di Maria, Emilio; Donato, Stefano Di; Kaemmerer, William F.

In: Experimental Neurology, Vol. 217, No. 2, 06.2009, p. 312-319.

Research output: Contribution to journalArticle

Lombardi, Maria Stella ; Jaspers, Leonie ; Spronkmans, Christine ; Gellera, Cinzia ; Taroni, Franco ; Di Maria, Emilio ; Donato, Stefano Di ; Kaemmerer, William F. / A majority of Huntington's disease patients may be treatable by individualized allele-specific RNA interference. In: Experimental Neurology. 2009 ; Vol. 217, No. 2. pp. 312-319.
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