{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,14]],"date-time":"2026-01-14T19:15:37Z","timestamp":1768418137034,"version":"3.49.0"},"reference-count":41,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2020,4,23]],"date-time":"2020-04-23T00:00:00Z","timestamp":1587600000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100008530","name":"European Regional Development Fund","doi-asserted-by":"publisher","award":["COMPETE: POCI-01-0145-FEDER-007440"],"award-info":[{"award-number":["COMPETE: POCI-01-0145-FEDER-007440"]}],"id":[{"id":"10.13039\/501100008530","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100008530","name":"European Regional Development Fund","doi-asserted-by":"publisher","award":["Norte-01-0145-FEDER-000008"],"award-info":[{"award-number":["Norte-01-0145-FEDER-000008"]}],"id":[{"id":"10.13039\/501100008530","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100008530","name":"European Regional Development Fund","doi-asserted-by":"publisher","award":["PPBI-POCI-01-0145-FEDER-022122"],"award-info":[{"award-number":["PPBI-POCI-01-0145-FEDER-022122"]}],"id":[{"id":"10.13039\/501100008530","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100008530","name":"European Regional Development Fund","doi-asserted-by":"publisher","award":["POCI-01-0145-FEDER-022184"],"award-info":[{"award-number":["POCI-01-0145-FEDER-022184"]}],"id":[{"id":"10.13039\/501100008530","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["FCT-ANR\/BEX-GMG\/0008\/2013"],"award-info":[{"award-number":["FCT-ANR\/BEX-GMG\/0008\/2013"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["SFRH\/BPD\/116046\/2016"],"award-info":[{"award-number":["SFRH\/BPD\/116046\/2016"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>Homozygous variants in MAG, encoding myelin-associated glycoprotein (MAG), have been associated with complicated forms of hereditary spastic paraplegia (HSP). MAG is a glycoprotein member of the immunoglobulin superfamily, expressed by myelination cells. In this study, we identified a novel homozygous missense variant in MAG (c.124T&gt;C; p.Cys42Arg) in a Portuguese family with early-onset autosomal recessive cerebellar ataxia with neuropathy and oculomotor apraxia. We used homozygosity mapping and exome sequencing to identify the MAG variant, and cellular studies to confirm its detrimental effect. Our results showed that this variant reduces protein stability and impairs the post-translational processing (N-linked glycosylation) and subcellular localization of MAG, thereby associating a loss of protein function with the phenotype. Therefore, MAG variants should be considered in the diagnosis of hereditary cerebellar ataxia with oculomotor apraxia, in addition to spastic paraplegia.<\/jats:p>","DOI":"10.3390\/jcm9041212","type":"journal-article","created":{"date-parts":[[2020,4,23]],"date-time":"2020-04-23T10:46:22Z","timestamp":1587638782000},"page":"1212","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Novel MAG Variant Causes Cerebellar Ataxia with Oculomotor Apraxia: Molecular Basis and Expanded Clinical Phenotype"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2343-2215","authenticated-orcid":false,"given":"Mariana","family":"Santos","sequence":"first","affiliation":[{"name":"UnIGENe, IBMC-Institute for Molecular and Cell Biology, i3S-Instituto de Investiga\u00e7\u00e3o e Inova\u00e7\u00e3o em Sa\u00fade, Universidade do Porto, 4200-135 Porto, Portugal"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6539-6398","authenticated-orcid":false,"given":"Joana","family":"Dam\u00e1sio","sequence":"additional","affiliation":[{"name":"UnIGENe, IBMC-Institute for Molecular and Cell Biology, i3S-Instituto de Investiga\u00e7\u00e3o e Inova\u00e7\u00e3o em Sa\u00fade, Universidade do Porto, 4200-135 Porto, Portugal"},{"name":"CGPP, IBMC-Institute for Molecular and Cell Biology, i3S-Instituto de Investiga\u00e7\u00e3o e Inova\u00e7\u00e3o em Sa\u00fade, Universidade do Porto, 4200-135 Porto, Portugal"},{"name":"Neurology Department, Centro Hospitalar do Porto, 4099-001 Porto, Portugal"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4528-0061","authenticated-orcid":false,"given":"C\u00e9lia","family":"Kun-Rodrigues","sequence":"additional","affiliation":[{"name":"Center for Neurodegenerative Science, Van Andel Institute, Grand Rapids, Michigan, MI 49503, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Clara","family":"Barbot","sequence":"additional","affiliation":[{"name":"CGPP, IBMC-Institute for Molecular and Cell Biology, i3S-Instituto de Investiga\u00e7\u00e3o e Inova\u00e7\u00e3o em Sa\u00fade, Universidade do Porto, 4200-135 Porto, Portugal"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9846-1037","authenticated-orcid":false,"given":"Jorge","family":"Sequeiros","sequence":"additional","affiliation":[{"name":"UnIGENe, IBMC-Institute for Molecular and Cell Biology, i3S-Instituto de Investiga\u00e7\u00e3o e Inova\u00e7\u00e3o em Sa\u00fade, Universidade do Porto, 4200-135 Porto, Portugal"},{"name":"CGPP, IBMC-Institute for Molecular and Cell Biology, i3S-Instituto de Investiga\u00e7\u00e3o e Inova\u00e7\u00e3o em Sa\u00fade, Universidade do Porto, 4200-135 Porto, Portugal"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jos\u00e9","family":"Br\u00e1s","sequence":"additional","affiliation":[{"name":"Center for Neurodegenerative Science, Van Andel Institute, Grand Rapids, Michigan, MI 49503, USA"},{"name":"Division of Psychiatry and Behavioral Medicine, Michigan State University College of Human Medicine, Grand Rapids, Michigan, MI 49503, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Isabel","family":"Alonso","sequence":"additional","affiliation":[{"name":"UnIGENe, IBMC-Institute for Molecular and Cell Biology, i3S-Instituto de Investiga\u00e7\u00e3o e Inova\u00e7\u00e3o em Sa\u00fade, Universidade do Porto, 4200-135 Porto, Portugal"},{"name":"CGPP, IBMC-Institute for Molecular and Cell Biology, i3S-Instituto de Investiga\u00e7\u00e3o e Inova\u00e7\u00e3o em Sa\u00fade, Universidade do Porto, 4200-135 Porto, Portugal"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5879-3486","authenticated-orcid":false,"given":"Rita","family":"Guerreiro","sequence":"additional","affiliation":[{"name":"Center for Neurodegenerative Science, Van Andel Institute, Grand Rapids, Michigan, MI 49503, USA"},{"name":"Division of Psychiatry and Behavioral Medicine, Michigan State University College of Human Medicine, Grand Rapids, Michigan, MI 49503, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,4,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"673","DOI":"10.1038\/gim.2013.28","article-title":"Hereditary ataxias: Overview","volume":"15","author":"Jayadev","year":"2013","journal-title":"Genet. 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