{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,27]],"date-time":"2025-11-27T16:18:52Z","timestamp":1764260332731,"version":"3.41.2"},"reference-count":28,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2024,2,13]],"date-time":"2024-02-13T00:00:00Z","timestamp":1707782400000},"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. Pediatr."],"abstract":"<jats:sec><jats:title>Background<\/jats:title><jats:p>Pathogenic variants in the <jats:italic>IGHMBP2<\/jats:italic> gene are associated with two distinct autosomal recessive neuromuscular disorders: spinal muscular atrophy with respiratory distress type 1 (SMARD1; OMIM #604320) and Charcot\u2013Marie\u2013Tooth type 2S (CMT2S; OMIM #616155). SMARD1 is a severe and fatal condition characterized by infantile-onset respiratory distress, diaphragmatic palsy, and distal muscular weakness, while CMT2S follows a milder clinical course, with slowly progressive distal muscle weakness and sensory loss, without manifestations of respiratory disorder.<\/jats:p><\/jats:sec><jats:sec><jats:title>Methods<\/jats:title><jats:p>Whole-exome sequencing of the <jats:italic>IGHMBP2<\/jats:italic> gene was performed for eight Vietnamese patients with <jats:italic>IGHMBP2<\/jats:italic>-related neuromuscular disorders including five patients with SMARD1 and the others with CMT2S.<\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p>We identified one novel <jats:italic>IGHMBP2<\/jats:italic> variant c.1574T\u2009&amp;gt;\u2009C (p.Leu525Pro) in a SMARD1 patient. Besides that, two patients shared the same pathogenic variants (c.1235\u2009+\u20093A\u2009&amp;gt;\u2009G\/c.1334A\u2009&amp;gt;\u2009C) but presented completely different clinical courses: one with SMARD1 who deceased at 8 months of age, the other with CMT2S was alive at 3 years old without any respiratory distress.<\/jats:p><\/jats:sec><jats:sec><jats:title>Conclusion<\/jats:title><jats:p>This study is the first to report <jats:italic>IGHMBP-2<\/jats:italic>-related neuromuscular disorders in Vietnam. A novel <jats:italic>IGHMBP2<\/jats:italic> variant c.1574T\u2009&amp;gt;\u2009C (p.Leu525Pro) expressing SMARD1 phenotype was detected. The presence of three patients with the same genotype but distinct clinical outcomes suggested the interaction of variants and other factors including relating modified genes in the mechanism of various phenotypes.<\/jats:p><\/jats:sec>","DOI":"10.3389\/fped.2024.1165492","type":"journal-article","created":{"date-parts":[[2024,2,13]],"date-time":"2024-02-13T04:36:39Z","timestamp":1707798999000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":4,"title":["A novel IGHMBP2 variant and clinical diversity in Vietnamese SMARD1 and CMT2S patients"],"prefix":"10.3389","volume":"12","author":[{"given":"Van Khanh","family":"Tran","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"My Ha","family":"Cao","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Thi Thanh 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