Display options
Share it on

Rare Dis. 2016 Feb 18;4(1):e1131885. doi: 10.1080/21675511.2015.1131885. eCollection 2016.

Problems and solutions for the analysis of somatic CAG repeat expansion and their relationship to Huntington's disease toxicity.

Rare diseases (Austin, Tex.)

Helen Budworth, Cynthia T McMurray

Affiliations

  1. Life Sciences Division, Lawrence Berkeley National Laboratory , Berkeley, CA, USA.

PMID: 27141411 PMCID: PMC4838321 DOI: 10.1080/21675511.2015.1131885

Abstract

Huntington's Disease is caused by inheritance of a single disease-length allele harboring an expanded CAG repeat, which continues to expand in somatic tissues with age. Whether somatic expansion contributed to toxicity was unknown. From extensive work from multiple laboratories, it has been made clear that toxicity depended on length of the inherited allele, but whether preventing or delaying somatic repeat expansion in vivo would be beneficial was unknown, since the inherited disease allele was still expressed. In Budworth et al., we provided definitive evidence that suppressing the somatic expansion in mice substantially delays disease onset in littermates that inherit the same disease-length allele. This key discovery opens the door for therapeutic approaches targeted at stopping or shortening the CAG tract during life. The analysis was difficult and, at times, non-standard. Here, we take the opportunity to discuss the challenges, the analytical solutions, and to address some controversial issues with respect to expansion biology.

Keywords: DNA repair; OGG1 DNA glycosylase; huntington's Disease; oxidative DNA damage; somatic expansion; trinucleotides; triplet repeat expansions

References

  1. Nat Genet. 1997 Feb;15(2):197-200 - PubMed
  2. Hum Mol Genet. 2007 May 15;16(10 ):1133-42 - PubMed
  3. Neurobiol Dis. 2009 Jan;33(1):37-47 - PubMed
  4. Front Genet. 2014 Aug 21;5:287 - PubMed
  5. Hum Mol Genet. 2002 Jan 15;11(2):191-8 - PubMed
  6. Nat Genet. 1993 Aug;4(4):398-403 - PubMed
  7. Nature. 2007 May 24;447(7143):447-52 - PubMed
  8. Hum Mol Genet. 1999 Jan;8(1):115-22 - PubMed
  9. Nat Rev Genet. 2010 Nov;11(11):786-99 - PubMed
  10. Nature. 2007 Jun 21;447(7147):932-40 - PubMed
  11. Nat Genet. 1999 Dec;23(4):471-3 - PubMed
  12. Hum Mol Genet. 2000 Oct 12;9(17):2539-44 - PubMed
  13. Hum Mol Genet. 2003 Feb 1;12 (3):273-81 - PubMed
  14. BMC Syst Biol. 2010 Mar 19;4:29 - PubMed
  15. J Neuropathol Exp Neurol. 1985 Nov;44(6):559-77 - PubMed
  16. PLoS Genet. 2010 Dec 09;6(12 ):e1001242 - PubMed
  17. J Neurosci. 1999 Apr 1;19(7):2522-34 - PubMed
  18. Hum Mol Genet. 2003 Dec 15;12 (24):3359-67 - PubMed
  19. EMBO J. 2003 May 1;22(9):2264-73 - PubMed
  20. Hum Mol Genet. 2009 Aug 15;18(16):3039-47 - PubMed
  21. Nat Struct Mol Biol. 2005 Aug;12(8):663-70 - PubMed
  22. PLoS Genet. 2015 Aug 06;11(8):e1005267 - PubMed

Publication Types

Grant support