{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,29]],"date-time":"2026-07-29T03:00:22Z","timestamp":1785294022544,"version":"3.55.0"},"reference-count":20,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2023,5,25]],"date-time":"2023-05-25T00:00:00Z","timestamp":1684972800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"University of Campania \u2018Luigi Vanvitelli\u2019"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Disrupting variants in the DMD gene are associated with Duchenne or Becker muscular dystrophy (DMD\/BMD) or with hyperCKemia, all of which present very different degrees of clinical severity. The clinical phenotypes of these disorders could not be distinguished in infancy or early childhood. Accurate phenotype prediction based on DNA variants may therefore be required in addition to invasive tests, such as muscle biopsy. Transposon insertion is one of the rarest mutation types. Depending on their position and characteristics, transposon insertions may affect the quality and\/or quantity of dystrophin mRNA, leading to unpredictable alterations in gene products. Here, we report the case of a three-year-old boy showing initial skeletal muscle involvement in whom we characterized a transposon insertion (Alu sequence) in exon 15 of the DMD gene. In similar cases, the generation of a null allele is predicted, resulting in a DMD phenotype. However, mRNA analysis of muscle biopsy tissue revealed skipping of exon 15, which restored the reading frame, thus predicting a milder phenotype. This case is similar to very few others already described in the literature. This case further enriches our knowledge of the mechanisms perturbing splicing and causing exon skipping in DMD, helping to properly guide clinical diagnosis.<\/jats:p>","DOI":"10.3390\/ijms24119241","type":"journal-article","created":{"date-parts":[[2023,5,26]],"date-time":"2023-05-26T02:05:44Z","timestamp":1685066744000},"page":"9241","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Alu-Mediated Insertions in the DMD Gene: A Difficult Puzzle to Interpret Clinically"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2479-6018","authenticated-orcid":false,"given":"Annalaura","family":"Torella","sequence":"first","affiliation":[{"name":"Department of Precision Medicine, University of Campania \u201cLuigi Vanvitelli\u201d, Via L. De Crecchio 7, 80138 Naples, Italy"},{"name":"Telethon Institute of Genetics and Medicine, Via Campi Flegrei 34, 80078 Pozzuoli, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-0889-4784","authenticated-orcid":false,"given":"Alberto","family":"Budillon","sequence":"additional","affiliation":[{"name":"Department of Precision Medicine, University of Campania \u201cLuigi Vanvitelli\u201d, Via L. De Crecchio 7, 80138 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3750-1592","authenticated-orcid":false,"given":"Mariateresa","family":"Zanobio","sequence":"additional","affiliation":[{"name":"Department of Precision Medicine, University of Campania \u201cLuigi Vanvitelli\u201d, Via L. De Crecchio 7, 80138 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Francesca","family":"Del Vecchio Blanco","sequence":"additional","affiliation":[{"name":"Department of Precision Medicine, University of Campania \u201cLuigi Vanvitelli\u201d, Via L. De Crecchio 7, 80138 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Esther","family":"Picillo","sequence":"additional","affiliation":[{"name":"Department of Precision Medicine, University of Campania \u201cLuigi Vanvitelli\u201d, Via L. De Crecchio 7, 80138 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0925-7158","authenticated-orcid":false,"given":"Luisa","family":"Politano","sequence":"additional","affiliation":[{"name":"Department of Experimental Medicine, University of Campania \u201cLuigi Vanvitelli\u201d, Via L. De Crecchio 7, 80138 Napoli, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3378-5006","authenticated-orcid":false,"given":"Vincenzo","family":"Nigro","sequence":"additional","affiliation":[{"name":"Department of Precision Medicine, University of Campania \u201cLuigi Vanvitelli\u201d, Via L. De Crecchio 7, 80138 Naples, Italy"},{"name":"Telethon Institute of Genetics and Medicine, Via Campi Flegrei 34, 80078 Pozzuoli, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9418-125X","authenticated-orcid":false,"given":"Giulio","family":"Piluso","sequence":"additional","affiliation":[{"name":"Department of Precision Medicine, University of Campania \u201cLuigi Vanvitelli\u201d, Via L. De Crecchio 7, 80138 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,5,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"585","DOI":"10.1016\/j.bbadis.2014.07.023","article-title":"Spectrum of muscular dystrophies associated with sarcolemmal-protein genetic defects","volume":"1852","author":"Nigro","year":"2015","journal-title":"Biochim. Biophys. Acta"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"671","DOI":"10.1016\/j.ncl.2014.05.002","article-title":"Duchenne and Becker muscular dystrophies","volume":"32","author":"Flanigan","year":"2014","journal-title":"Neurol. Clin."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"131","DOI":"10.3389\/fgene.2020.00131","article-title":"The Genetic Landscape of Dystrophin Mutations in Italy: A Nationwide Study","volume":"11","author":"Neri","year":"2020","journal-title":"Front. 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