A rare X-linked syndromic intellectual disability characterized by severe to profound intellectual disability muscular hypotonia in childhood delayed walking delayed or minimal/absent speech behavioral abnormalities including aggressiveness agitation and self-injurious behavior and dysmorphic facial features (such as triangular face with high forehead prominent ears and small pointed chin). Additional reported manifestations include microcephaly short stature and seizures among others.
Data from Orphanet are used to provide information on a disease's name, synonym(s), and overview. Reference: Access aggregated data from Orphanet at Orphadata. Orphadata: Free access data from Orphanet. © INSERM 1999. Available on http://www.orphadata.org. Data version February 2026
Newly diagnosed with
X-linked intellectual disability-hypotonia-facial dysmorphism-aggressive behavior syndrome?
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