{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,28]],"date-time":"2026-01-28T02:56:16Z","timestamp":1769568976597,"version":"3.49.0"},"reference-count":26,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2023,5,5]],"date-time":"2023-05-05T00:00:00Z","timestamp":1683244800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Neurol."],"abstract":"<jats:sec><jats:title>Background<\/jats:title><jats:p>Intellectual disability, X-linked, syndromic, Christianson type (MRXSCH, OMIM: 300243)\u2014known as Christianson syndrome (CS)\u2014is characterized by microcephaly, epilepsy, ataxia, and absence of verbal language ability. CS is attributed to mutations in the solute carrier family 9 member A6 gene (<jats:italic>SLC9A6<\/jats:italic>).<\/jats:p><\/jats:sec><jats:sec><jats:title>Materials and methods<\/jats:title><jats:p>This study reports the case of a boy 1\u2009year and 3\u2009months of age who was diagnosed with CS in our department. Genetic etiology was determined by whole-exome sequencing, and a minigene splicing assay was used to verify whether the mutation affected splicing. A literature review of CS cases was conducted and the clinical and genetic features were summarized.<\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p>The main clinical manifestations of CS include seizures, developmental regression, and exceptional facial features. Whole-exome sequencing revealed a <jats:italic>de novo<\/jats:italic> splice variant in intron 11 (c.1366\u2009+\u20091G\u2009&amp;gt;\u2009C) of <jats:italic>SLC9A6<\/jats:italic>. The mutation produced two abnormal mRNA products (verified by a minigene splicing assay), resulting in the formation of truncated protein. A total of 95 CS cases were identified in the literature, with various symptoms, such as delayed intellectual development (95\/95, 100.00%), epilepsy (87\/88, 98.86%), and absent verbal language (75\/83, 90.36%). At least 50 pathogenic variants of <jats:italic>SLC9A6<\/jats:italic> have been identified, with the highest frequency observed in exon 12.<\/jats:p><\/jats:sec><jats:sec><jats:title>Conclusion<\/jats:title><jats:p>Our patient is the first case with the c.1366\u2009+\u20091G\u2009&amp;gt;\u2009C variant of <jats:italic>SLC9A6<\/jats:italic> in CS. The summary of known cases can serve as a reference for analyzing the mutation spectrum and pathogenesis of CS.<\/jats:p><\/jats:sec>","DOI":"10.3389\/fneur.2023.1152696","type":"journal-article","created":{"date-parts":[[2023,5,5]],"date-time":"2023-05-05T06:04:40Z","timestamp":1683266680000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":4,"title":["Clinical and genetic analysis of Christianson syndrome caused by variant of SLC9A6: case report and literature review"],"prefix":"10.3389","volume":"14","author":[{"given":"Yan","family":"Dong","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ruofei","family":"Lian","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Liang","family":"Jin","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shichao","family":"Zhao","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wenpeng","family":"Tao","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lijun","family":"Wang","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mengchun","family":"Li","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tianming","family":"Jia","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xuejing","family":"Chen","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shushi","family":"Cao","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1965","published-online":{"date-parts":[[2023,5,5]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"97","DOI":"10.1016\/j.neuron.2013.07.043","article-title":"Christianson 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