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FG syndrome 4

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The information provided on this page is for informational purposes only. The National Organization for Rare Disorders (NORD) does not endorse the information presented. The content has been gathered in partnership with the MONDO Disease Ontology. Please consult with a healthcare professional for medical advice and treatment.

Disease Overview

FG syndrome-4 (FGS4) is an X-linked recessive intellectual developmental disorder characterized by congenital hypotonia, constipation, behavioral disturbances, and dysmorphic features. [OMIM]

Note:  According to GR it seems more appropriate to subsume the phenotype described in these families under XLID with or without nystagmus. (https://www.ncbi.nlm.nih.gov/books/NBK169825/)

Synonyms

  • X-linked intellectual disability (XLID) with or without nystagmus
  • FG syndrome caused by CASK variants
  • CASK-related FG syndrome
OMIM

Online Mendelian Inheritance In Man (OMIM) has a summary of published research about this condition and includes references from the medical literature. The summary contains medical and scientific terms, so we encourage you to share and discuss this information with your doctor. OMIM is authored and edited at the McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine.

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