{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T15:55:03Z","timestamp":1787241303358,"version":"build-2736575974"},"reference-count":50,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2024,4,22]],"date-time":"2024-04-22T00:00:00Z","timestamp":1713744000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biomolecules"],"abstract":"<jats:p>Andersen\u2013Tawil syndrome (ATS) is a multisystem channelopathy characterized by periodic paralysis, ventricular arrhythmias, prolonged QT interval, and facial dysmorphisms occurring in the first\/second decade of life. High phenotypic variability and incomplete penetrance of the genes causing the disease make its diagnosis still a challenge. We describe a three-generation family with six living individuals affected by ATS. The proband is a 37-year-old woman presenting since age 16, with episodes of muscle weakness and cramps in the pre-menstrual period. The father, two brothers, one paternal uncle and one cousin also complained of cramps, muscle stiffness, and weakness. Despite normal serum potassium concentration, treatment with potassium, magnesium, and acetazolamide alleviated paralysis attacks suggesting a dyskalemic syndrome. Dysmorphic features were noted in the proband, only later. On the ECG, all but one had normal QT intervals. The affected males developed metabolic syndrome or obesity. The father had two myocardial infarctions and was implanted with an intracardiac cardioverter defibrillator (ICD). A genetic investigation by WES analysis detected the heterozygous pathogenic variant (NM_000891.2: c.652C&gt;T, p. Arg218Trp) in the KCNJ2 gene related to ATS, confirmed by segregation studies in all affected members. Furthermore, we performed a review of cases with the same mutation in the literature, looking for similarities and divergences with our family case.<\/jats:p>","DOI":"10.3390\/biom14040507","type":"journal-article","created":{"date-parts":[[2024,4,22]],"date-time":"2024-04-22T07:44:09Z","timestamp":1713771849000},"page":"507","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Phenotypic Variability of Andersen\u2013Tawil Syndrome Due to Allelic Mutation c.652C&gt;T in the KCNJ2 Gene\u2014A New Family Case Report"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8329-0215","authenticated-orcid":false,"given":"Maria Elena","family":"Onore","sequence":"first","affiliation":[{"name":"Department of Precision Medicine, University of Campania \u201cLuigi Vanvitelli\u201d, 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, 80138 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Paola","family":"D\u2019Ambrosio","sequence":"additional","affiliation":[{"name":"Cardiomyology and Medical Genetics Unit, University of Campania \u201cLuigi Vanvitelli\u201d, 80138 Napoli, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Salvatore","family":"Morra","sequence":"additional","affiliation":[{"name":"Department of Precision Medicine, University of Campania \u201cLuigi Vanvitelli\u201d, 80138 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vincenzo","family":"Nigro","sequence":"additional","affiliation":[{"name":"Department of Precision Medicine, University of Campania \u201cLuigi Vanvitelli\u201d, 80138 Naples, Italy"},{"name":"Telethon Institute of Genetics and Medicine (TIGEM), 80078 Pozzuoli, 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":"Cardiomyology and Medical Genetics Unit, University of Campania \u201cLuigi Vanvitelli\u201d, 80138 Napoli, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,4,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"196","DOI":"10.1136\/practneurol-2020-002576","article-title":"Skeletal muscle channelopathies: A guide to diagnosis and management","volume":"21","author":"Matthews","year":"2021","journal-title":"Pract. 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