{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,19]],"date-time":"2026-06-19T23:59:45Z","timestamp":1781913585440,"version":"3.54.5"},"reference-count":37,"publisher":"MDPI AG","issue":"20","license":[{"start":{"date-parts":[[2023,10,11]],"date-time":"2023-10-11T00:00:00Z","timestamp":1696982400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ricerca Corrente funding from the Italian Ministry of Health to IRCCS Policlinico San Donato","award":["2016-CONT-0494"],"award-info":[{"award-number":["2016-CONT-0494"]}]},{"name":"Ricerca Corrente funding from the Italian Ministry of Health to IRCCS Policlinico San Donato","award":["2016-CONT-0494"],"award-info":[{"award-number":["2016-CONT-0494"]}]},{"name":"University of Milano-Bicocca","award":["2016-CONT-0494"],"award-info":[{"award-number":["2016-CONT-0494"]}]},{"name":"University of Milano-Bicocca","award":["2016-CONT-0494"],"award-info":[{"award-number":["2016-CONT-0494"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Brugada Syndrome (BrS) is a rare inherited cardiac arrhythmia causing potentially fatal ventricular tachycardia or fibrillation, mainly occurring during rest or sleep in young individuals without heart structural issues. It increases the risk of sudden cardiac death, and its characteristic feature is an abnormal ST segment elevation on the ECG. While BrS has diverse genetic origins, a subset of cases can be conducted to mutations in the SCN5A gene, which encodes for the Nav1.5 sodium channel. Our study focused on three novel SCN5A mutations (p.A344S, p.N347K, and p.D349N) found in unrelated BrS families. Using patch clamp experiments, we found that these mutations disrupted sodium currents: p.A344S reduced current density, while p.N347K and p.D349N completely abolished it, leading to altered voltage dependence and inactivation kinetics when co-expressed with normal channels. We also explored the effects of mexiletine treatment, which can modulate ion channel function. Interestingly, the p.N347K and p.D349N mutations responded well to the treatment, rescuing the current density, while p.A344S showed a limited response. Structural analysis revealed these mutations were positioned in key regions of the channel, impacting its stability and function. This research deepens our understanding of BrS by uncovering the complex relationship between genetic mutations, ion channel behavior, and potential therapeutic interventions.<\/jats:p>","DOI":"10.3390\/ijms242015089","type":"journal-article","created":{"date-parts":[[2023,10,12]],"date-time":"2023-10-12T03:07:47Z","timestamp":1697080067000},"page":"15089","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Unravelling Novel SCN5A Mutations Linked to Brugada Syndrome: Functional, Structural, and Genetic Insights"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7628-989X","authenticated-orcid":false,"given":"Anthony","family":"Frosio","sequence":"first","affiliation":[{"name":"Institute of Molecular and Translational Cardiology (IMTC), IRCCS Policlinico San Donato, 20097 San Donato Milanese, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8298-7800","authenticated-orcid":false,"given":"Emanuele","family":"Micaglio","sequence":"additional","affiliation":[{"name":"Institute of Molecular and Translational Cardiology (IMTC), IRCCS Policlinico San Donato, 20097 San Donato Milanese, Italy"},{"name":"Arrhythmia and Electrophysiology Department, IRCCS Policlinico San Donato, 20097 San Donato Milanese, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3664-0264","authenticated-orcid":false,"given":"Ivan","family":"Polsinelli","sequence":"additional","affiliation":[{"name":"Institute of Molecular and Translational Cardiology (IMTC), IRCCS Policlinico San Donato, 20097 San Donato Milanese, 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20132 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6678-5873","authenticated-orcid":false,"given":"Stefano","family":"Ricagno","sequence":"additional","affiliation":[{"name":"Institute of Molecular and Translational Cardiology (IMTC), IRCCS Policlinico San Donato, 20097 San Donato Milanese, Italy"},{"name":"Department of Biosciences, Universit\u00e0 degli Studi di Milano, Via Celoria, 26, 20133 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Carlo","family":"Pappone","sequence":"additional","affiliation":[{"name":"Institute of Molecular and Translational Cardiology (IMTC), IRCCS Policlinico San Donato, 20097 San Donato Milanese, Italy"},{"name":"Arrhythmia and Electrophysiology Department, IRCCS Policlinico San Donato, 20097 San Donato Milanese, Italy"},{"name":"Faculty of Medicine and Surgery, Vita-Salute San Raffaele University, Via Olgettina, 58, 20132 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7411-9069","authenticated-orcid":false,"given":"Ilaria","family":"Rivolta","sequence":"additional","affiliation":[{"name":"Institute of Molecular and Translational Cardiology (IMTC), IRCCS Policlinico San Donato, 20097 San Donato Milanese, Italy"},{"name":"School of Medicine and Surgery, University of Milano-Bicocca, Via Cadore, 48, 20900 Monza, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,10,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"13","DOI":"10.15420\/aer.2018.73.2","article-title":"Brugada Syndrome: Progress in Diagnosis and Management","volume":"8","author":"Pappone","year":"2019","journal-title":"Arrhythmia Electrophysiol. 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