{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,28]],"date-time":"2026-10-28T22:47:31Z","timestamp":1793227651704,"version":"4.5.0"},"reference-count":109,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2021,7,9]],"date-time":"2021-07-09T00:00:00Z","timestamp":1625788800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Brain Sciences"],"abstract":"<jats:p>Nearly 20% of genes located on the X chromosome are associated with neurodevelopmental disorders (NDD) due to their expression and role in brain functioning. Given their location, several of these genes are either subject to or can escape X-chromosome inactivation (XCI). The degree to which genes are subject to XCI can influence the NDD phenotype between males and females. We provide a general review of X-linked NDD genes in the context of XCI and detailed discussion of the sex-based differences related to MECP2 and FMR1, two common X-linked causes of NDD that are subject to XCI. Understanding the effects of XCI on phenotypic expression of NDD genes may guide the development of stratification biomarkers in X-linked disorders.<\/jats:p>","DOI":"10.3390\/brainsci11070904","type":"journal-article","created":{"date-parts":[[2021,7,9]],"date-time":"2021-07-09T04:14:57Z","timestamp":1625804097000},"page":"904","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":40,"title":["The Impact of X-Chromosome Inactivation on Phenotypic Expression of X-Linked Neurodevelopmental Disorders"],"prefix":"10.3390","volume":"11","author":[{"given":"Boudewien A","family":"Brand","sequence":"first","affiliation":[{"name":"Center for Autism and Related Disorders, Kennedy Krieger Institute, Baltimore, MD 21205, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alyssa E","family":"Blesson","sequence":"additional","affiliation":[{"name":"Center for Autism and Related Disorders, Kennedy Krieger Institute, Baltimore, MD 21205, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Constance L.","family":"Smith-Hicks","sequence":"additional","affiliation":[{"name":"Department of Neurology and Developmental Medicine, Kennedy Krieger Institute, Baltimore, MD 21205, USA"},{"name":"Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,7,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"205","DOI":"10.1086\/511441","article-title":"The Role of Neuronal Complexes in Human X-Linked Brain Diseases","volume":"80","author":"Laumonnier","year":"2007","journal-title":"Am. 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