GFP Reporters to Monitor Instability and Expression of Expanded CAG/CTG Repeats

  • Cinzia Cinesi
  • Bin Yang
  • Vincent DionEmail author
Part of the Methods in Molecular Biology book series (MIMB, volume 2056)


Expanded CAG/CTG repeats are genetically unstable and, upon expression, cause neurological and neuromuscular diseases. The molecular mechanisms of repeat instability and expression remain poorly understood despite their importance for the pathogenesis of a family of 14 devastating human diseases. This is in part because conventional assays are tedious and time-consuming. Recently, however, GFP-based reporters have been designed to provide a rapid and reliable means of assessing these parameters. Here we provide protocols for quantifying repeat instability and expression using a GFP-based chromosomal reporter and the newly developed ParB/ANCHOR-mediated Inducible Targeting (PInT) and how to validate the results.


Expanded CAG/CTG repeat diseases GFP reporters Gene expression Genome stability DNA repair 



We thank members of Joachim Lingner’s lab for help setting up the ChIP protocol and Dinis Barros for help with the figures. This work is supported by Swiss National Foundation professorships (#172936) to V.D. and by the UK Dementia Research Institute, which receives its funding from DRI Ltd, funded by the UK Medical Research Council, Alzheimer’s Society and Alzheimer’s Research UK.


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2020

Authors and Affiliations

  1. 1.Center for Integrative GenomicsUniversity of LausanneLausanneSwitzerland
  2. 2.Dementia Research InstituteCardiff UniversityCardiffUK

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