49,XYYYY syndrome
A rare Y chromosome number anomaly with a variable phenotype mainly characterized by moderate to severe intellectual disability speech delay hypotonia and mild dysmorphic features including facial asymmetry hypertelorism bilateral low set ‘lop’ ears and micrognatia. Skeletal abnormalities (such as skull deformities radioulnar synostosis elbow flexion clinodactyly brachydactyly) and behavourial problems have also been associated with this condition. Genitalia are normal at birth although hypogonadism and azoospermia has been reported in adults.
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 December 2023
Newly diagnosed with
49,XYYYY syndrome?
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Advocacy Organizations
Rare Chromosome Disorder Support Group – Unique
To inform, support and alleviate the isolation of anyone affected by a rare chromosome or single gene disorder and to raise public awareness.
Syndromes Without A Name (SWAN) Australia
Provide information, support and advocacy to families caring for a child with an undiagnosed or rare genetic condition.
Clinical Trials
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