Abstract
Different interrupted repeat expansions have been found in several trinucleotide repeat (TNR) diseases such as fragile X syndrome (FXS), spinocerebellar ataxias (SCAs), and myotonic dystrophies (DMs). Their origins and roles remain poorly understood, especially in myotonic dystrophy type 1 (DM1). We present here the triplet repeat primed polymerase chain reaction (TP-PCR) and restriction enzyme-digested PCR to detect and identify interrupted triplet repeat alleles in DM1. TP-PCR consists of a PCR amplification using a fluoresceinated (FAM) primer flanking the repeat region and a primer pair in CTG.CAG repeats. A detailed analysis of interrupted triplet repeat tracts is essential to fully understand the role of interruptions in the pathogenesis and molecular mechanisms observed in TNR diseases.
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Acknowledgments
The authors would like to thank Anchel González Barriga for helpful discussion and comments. This work was supported by Institut National de la Santé et de la recherche Médicale (INSERM), Université Paris Descartes, and AFM-Téléthon (project number 16331 and 19757). This program received a state subsidy managed by the National Research Agency under the “Investments for the Future” program bearing the reference ANR-10-IAHU-01.
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Tomé, S., Gourdon, G. (2020). Fast Assays to Detect Interruptions in CTG.CAG Repeat Expansions. In: Richard, GF. (eds) Trinucleotide Repeats. Methods in Molecular Biology, vol 2056. Humana, New York, NY. https://doi.org/10.1007/978-1-4939-9784-8_2
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DOI: https://doi.org/10.1007/978-1-4939-9784-8_2
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