{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,31]],"date-time":"2026-10-31T05:05:51Z","timestamp":1793423151811,"version":"4.5.0"},"reference-count":67,"publisher":"SAGE Publications","issue":"1","license":[{"start":{"date-parts":[[2021,2,9]],"date-time":"2021-02-09T00:00:00Z","timestamp":1612828800000},"content-version":"unspecified","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"content-domain":{"domain":["journals.sagepub.com"],"crossmark-restriction":true},"short-container-title":["Journal of Huntington's Disease"],"published-print":{"date-parts":[[2021,2,9]]},"abstract":"<jats:sec>\n                    <jats:title>Background:<\/jats:title>\n                    <jats:p>Huntington\u2019s disease (HD) is an autosomal dominant neurodegenerative disorder caused by the expansion of the HTT CAG repeat. Affected individuals inherit \u226536 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.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Objective:<\/jats:title>\n                    <jats:p>To investigate the utility of PCR sequencing to genotype large (&gt;50 CAGs) HD alleles and to quantify the associated somatic mosaicism.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods:<\/jats:title>\n                    <jats:p>We have applied MiSeq and PacBio sequencing to PCR products of the HTT CAG repeat in transgenic R6\/2 mice carrying \u223c55, \u223c110, \u223c255 and \u223c470 CAGs. For each of these alleles, we compared the repeat length distributions generated for different tissues at two ages.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results:<\/jats:title>\n                    <jats:p>We were able to sequence the CAG repeat full length in all samples. However, the repeat length distributions for samples with \u223c470 CAGs were biased towards shorter repeat lengths.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion:<\/jats:title>\n                    <jats:p>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 \u2aa2250 CAGs. We review the limitations of PCR sequencing and alternative approaches that may allow the quantification of somatic contractions and very large somatic expansions.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3233\/jhd-200433","type":"journal-article","created":{"date-parts":[[2021,2,9]],"date-time":"2021-02-09T21:42:07Z","timestamp":1612906927000},"page":"53-74","update-policy":"https:\/\/doi.org\/10.1177\/sage-journals-update-policy","source":"Crossref","is-referenced-by-count":35,"title":["Approaches to Sequence the\n                    <i>HTT<\/i>\n                    CAG Repeat Expansion and Quantify Repeat Length Variation"],"prefix":"10.1177","volume":"10","author":[{"given":"Marc","family":"Ciosi","sequence":"first","affiliation":[{"name":"Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sarah A.","family":"Cumming","sequence":"additional","affiliation":[{"name":"Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Afroditi","family":"Chatzi","sequence":"additional","affiliation":[{"name":"Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eloise","family":"Larson","sequence":"additional","affiliation":[{"name":"Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"William","family":"Tottey","sequence":"additional","affiliation":[{"name":"Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vilija","family":"Lomeikaite","sequence":"additional","affiliation":[{"name":"Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Graham","family":"Hamilton","sequence":"additional","affiliation":[{"name":"Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK"},{"name":"Glasgow Polyomics, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vanessa C.","family":"Wheeler","sequence":"additional","affiliation":[{"name":"Molecular Neurogenetics Unit, Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, USA"},{"name":"Department of Neurology, Harvard Medical School, Boston, MA, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ricardo Mouro","family":"Pinto","sequence":"additional","affiliation":[{"name":"Molecular Neurogenetics Unit, Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, USA"},{"name":"Department of Neurology, Harvard Medical School, Boston, MA, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Seung","family":"Kwak","sequence":"additional","affiliation":[{"name":"CHDI Management\/CHDI Foundation, Princeton, NJ, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"A. Jennifer","family":"Morton","sequence":"additional","affiliation":[{"name":"Department of Physiology, Development and Neuroscience, University of Cambridge, Tennis Court Road, Cambridge, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Darren G.","family":"Monckton","sequence":"additional","affiliation":[{"name":"Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"179","published-online":{"date-parts":[[2021,2,9]]},"reference":[{"key":"ref001","doi-asserted-by":"publisher","DOI":"10.1212\/wnl.0000000000005690"},{"key":"ref002","doi-asserted-by":"publisher","DOI":"10.3233\/JHD-200445"},{"key":"ref003","doi-asserted-by":"publisher","DOI":"10.3233\/JHD-200427"},{"key":"ref004","doi-asserted-by":"publisher","DOI":"10.1038\/ng0893-387"},{"key":"ref005","doi-asserted-by":"publisher","DOI":"10.3233\/JHD-200429"},{"key":"ref006","doi-asserted-by":"publisher","DOI":"10.1093\/hmg\/ddm054"},{"key":"ref007","doi-asserted-by":"publisher","DOI":"10.1016\/j.ebiom.2019.09.020"},{"key":"ref008","doi-asserted-by":"publisher","DOI":"10.1016\/j.dnarep.2007.01.002"},{"key":"ref009","doi-asserted-by":"publisher","DOI":"10.1093\/hmg\/ddg352"},{"key":"ref010","doi-asserted-by":"publisher","DOI":"10.1093\/hmg\/ddaa139"},{"key":"ref011","doi-asserted-by":"publisher","DOI":"10.1038\/ng0494-409"},{"key":"ref012","doi-asserted-by":"publisher","DOI":"10.3233\/JHD-200426"},{"key":"ref013","doi-asserted-by":"publisher","DOI":"10.1016\/B978-0-12-381328-2.00014-6"},{"key":"ref014","doi-asserted-by":"publisher","DOI":"10.1093\/hmg\/ddp242"},{"key":"ref015","doi-asserted-by":"publisher","DOI":"10.1093\/brain\/awz115"},{"key":"ref016","doi-asserted-by":"publisher","DOI":"10.1016\/j.cell.2019.06.036"},{"key":"ref017","doi-asserted-by":"publisher","DOI":"10.1016\/S1474-4422(17)30161-8"},{"key":"ref018","doi-asserted-by":"publisher","DOI":"10.3233\/JHD-200438"},{"key":"ref019","doi-asserted-by":"publisher","DOI":"10.3233\/JHD-200414"},{"key":"ref020","doi-asserted-by":"publisher","DOI":"10.1038\/70598"},{"key":"ref021","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pgen.1003280"},{"key":"ref022","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pgen.1003930"},{"key":"ref023","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0044273"},{"key":"ref024","doi-asserted-by":"publisher","DOI":"10.3233\/JHD-200414"},{"key":"ref025","doi-asserted-by":"publisher","DOI":"10.3233\/JHD-200448"},{"key":"ref026","doi-asserted-by":"publisher","DOI":"10.1007\/978-1-4939-7825-0_22"},{"key":"ref027","doi-asserted-by":"publisher","DOI":"10.1016\/j.ajhg.2019.04.007"},{"key":"ref028","doi-asserted-by":"publisher","DOI":"10.1373\/clinchem.2014.223677"},{"key":"ref029","doi-asserted-by":"publisher","DOI":"10.3390\/genes6010046"},{"key":"ref030","doi-asserted-by":"publisher","DOI":"10.1038\/s41431-018-0156-9"},{"key":"ref031","doi-asserted-by":"publisher","DOI":"10.1038\/s41436-019-0453-x"},{"key":"ref032","doi-asserted-by":"publisher","DOI":"10.1002\/ana.24656"},{"key":"ref033","doi-asserted-by":"publisher","DOI":"10.1016\/j.nbd.2015.01.004"},{"key":"ref034","doi-asserted-by":"publisher","DOI":"10.1016\/s0092-8674(00)81369-0"},{"key":"ref035","doi-asserted-by":"publisher","DOI":"10.1016\/j.nbd.2008.11.015"},{"key":"ref036","doi-asserted-by":"publisher","DOI":"10.3233\/jhd-170265"},{"key":"ref037","doi-asserted-by":"publisher","DOI":"10.1038\/s41598-018-37102-8"},{"key":"ref038","doi-asserted-by":"publisher","DOI":"10.1038\/protex.2018.089"},{"key":"ref039","unstructured":"PacBio. 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