Approaches to Sequence the HTT CAG Repeat Expansion and Quantify Repeat Length Variation
| العنوان: | Approaches to Sequence the HTT CAG Repeat Expansion and Quantify Repeat Length Variation |
|---|---|
| المؤلفون: | Seung Kwak, Sarah A. Cumming, Darren G. Monckton, Ricardo Mouro Pinto, Graham Hamilton, A. Jennifer Morton, Eloise Larson, Vanessa C. Wheeler, William Tottey, Marc Ciosi, Afroditi Chatzi, Vilija Lomeikaite |
| المساهمون: | Morton, Jennifer [0000-0003-0181-6346], Apollo - University of Cambridge Repository |
| المصدر: | Journal of Huntington's Disease |
| بيانات النشر: | IOS Press, 2021. |
| سنة النشر: | 2021 |
| مصطلحات موضوعية: | 0301 basic medicine, Research Report, congenital, hereditary, and neonatal diseases and abnormalities, Huntingtin, Somatic cell, huntingtin, repeat expansion, Mice, Transgenic, Biology, Polymerase Chain Reaction, 03 medical and health sciences, Cellular and Molecular Neuroscience, Mice, 0302 clinical medicine, Huntington's disease, Genotype, mental disorders, medicine, Animals, Allele, Sequence (medicine), Genetics, Huntingtin Protein, Massive parallel sequencing, Mosaicism, parallel sequencing, Sequence Analysis, DNA, Huntington disease, medicine.disease, Somatic mosaicism, nervous system diseases, 030104 developmental biology, Neurology (clinical), Trinucleotide repeat expansion, Trinucleotide Repeat Expansion, 030217 neurology & neurosurgery |
| الوصف: | Background:\ud Huntington’s disease (HD) is an autosomal dominant neurodegenerative disorder caused by the expansion of the HTT CAG repeat. Affected individuals inherit ≥36 repeats and longer alleles cause earlier onset, greater disease severity and faster disease progression. The HTT CAG repeat is genetically unstable in the soma in a process that preferentially generates somatic expansions, the proportion of which is associated with disease onset, severity and progression. Somatic mosaicism of the HTT CAG repeat has traditionally been assessed by semi-quantitative PCR-electrophoresis approaches that have limitations (e.g., no information about sequence variants). Genotyping-by-sequencing could allow for some of these limitations to be overcome.\ud \ud Objective:\ud To investigate the utility of PCR sequencing to genotype large (>50 CAGs) HD alleles and to quantify the associated somatic mosaicism.\ud \ud Methods:\ud We have applied MiSeq and PacBio sequencing to PCR products of the HTT CAG repeat in transgenic R6/2 mice carrying ∼55, ∼110, ∼255 and ∼470 CAGs. For each of these alleles, we compared the repeat length distributions generated for different tissues at two ages.\ud \ud Results:\ud We were able to sequence the CAG repeat full length in all samples. However, the repeat length distributions for samples with ∼470 CAGs were biased towards shorter repeat lengths.\ud \ud Conclusion:\ud PCR sequencing can be used to sequence all the HD alleles considered, but this approach cannot be used to estimate modal allele size or quantify somatic expansions for alleles ⪢250 CAGs. We review the limitations of PCR sequencing and alternative approaches that may allow the quantification of somatic contractions and very large somatic expansions. |
| وصف الملف: | application/pdf |
| اللغة: | English |
| تدمد: | 1879-6400 1879-6397 |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::4135c47bd75f6b3caba1c15107217c3b http://europepmc.org/articles/PMC7990409 |
| Rights: | OPEN |
| رقم الانضمام: | edsair.doi.dedup.....4135c47bd75f6b3caba1c15107217c3b |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 18796400 18796397 |
|---|