{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,9]],"date-time":"2026-09-09T07:32:03Z","timestamp":1788939123866,"version":"build-2803163510"},"reference-count":28,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2025,6,13]],"date-time":"2025-06-13T00:00:00Z","timestamp":1749772800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"This research was partially funded by the Italian Ministry of Health"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Genes"],"abstract":"<jats:p>Background\/Objectives: Joubert syndrome (JS, MIM 213300) is a rare genetic condition characterized by respiratory control disturbances, abnormal eye movements, ataxia, cognitive impairment, and the notable agenesis of the cerebellar vermis. The molar tooth sign visible in magnetic resonance imaging of the brain serves as a diagnostic tool for JS. Variants in the TCTN3 gene can lead to the development of several diseases, including JS type 18, Orofaciodigital syndrome IV, and Meckel\u2013Gruber syndrome. Methods: We performed whole-exome sequencing (WES) in a 49-year-old woman with JS characterized by severe intellectual disability, ataxic gait, agenesis of the cerebellar vermis leading to the molar tooth sign, dystonic movements, strabismus, and nystagmus. Moreover, the patient also showed a thickened corpus callosum. Results: Molecular analysis through WES revealed the heterozygous variants c.182dup (p.G62Wfs*18) and c.1452+4del in the TCTN3 gene, expanding our understanding of the genetic diversity and potential phenotypic implications associated with TCTN3 variations. Conclusions: To our knowledge, this is the first patient with JS and a thickened corpus callosum. Moreover, a thickened corpus callosum has never been identified in patients with pathogenic variants of the TCTN3 gene.<\/jats:p>","DOI":"10.3390\/genes16060706","type":"journal-article","created":{"date-parts":[[2025,6,16]],"date-time":"2025-06-16T14:03:11Z","timestamp":1750082591000},"page":"706","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Expansion of the Genotypic and Phenotypic Spectrum of TCTN3-Related Joubert Syndrome"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5961-0362","authenticated-orcid":false,"given":"Mariangela","family":"Lo Giudice","sequence":"first","affiliation":[{"name":"Oasi Research Institute\u2014IRCCS, Via Conte Ruggero 73, 94018 Troina, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5458-7415","authenticated-orcid":false,"given":"Eugenia","family":"Borgione","sequence":"additional","affiliation":[{"name":"Oasi Research Institute\u2014IRCCS, Via Conte Ruggero 73, 94018 Troina, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5083-1174","authenticated-orcid":false,"given":"Marika","family":"Giuliano","sequence":"additional","affiliation":[{"name":"Oasi Research Institute\u2014IRCCS, Via Conte Ruggero 73, 94018 Troina, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3310-782X","authenticated-orcid":false,"given":"Sandro","family":"Santa Paola","sequence":"additional","affiliation":[{"name":"Oasi Research Institute\u2014IRCCS, Via Conte Ruggero 73, 94018 Troina, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2958-2927","authenticated-orcid":false,"given":"Francesco Domenico","family":"Di Blasi","sequence":"additional","affiliation":[{"name":"Oasi Research Institute\u2014IRCCS, Via Conte Ruggero 73, 94018 Troina, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rosa","family":"Pettinato","sequence":"additional","affiliation":[{"name":"Oasi Research Institute\u2014IRCCS, Via Conte Ruggero 73, 94018 Troina, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1049-0683","authenticated-orcid":false,"given":"Corrado","family":"Romano","sequence":"additional","affiliation":[{"name":"Oasi Research Institute\u2014IRCCS, Via Conte Ruggero 73, 94018 Troina, Italy"},{"name":"Section of Clinical Biochemistry and Medical Genetics, Department of Biomedical and Biotechnological Sciences, University of Catania, 95123 Catania, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Carmela","family":"Scuderi","sequence":"additional","affiliation":[{"name":"Oasi Research Institute\u2014IRCCS, Via Conte Ruggero 73, 94018 Troina, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,6,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"813","DOI":"10.1212\/WNL.19.9.813","article-title":"Familial Agenesis of the Cerebellar Vermis. 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