SYNGAP1-related non-syndromic intellectual disability; MRD5; Syngap1 Gene Mutation Linked To Intellectual Disability, Schizophrenia and Autism; SYNGAP1syndrome; Autosomal dominant intellectual disability 5

SYNGAP1-related NSID is a condition that primarily affects the central nervous system. This condition is caused by changes (mutations) in the SYNGAP1 gene. Almost all reported cases are due to de novo mutations; however, the condition can be passed down to future generations in an autosomal dominant manner. Treatment is based on the signs and symptoms present in each person.

Diagnostic testing:Genetic testing is the only way to confirm a diagnosis of SYNGAP1-related NSID. However, an EEG may be used to support the diagnosis.

Physical findings:

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  Epileptic encephalopathy;

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  Microcephaly (abnormally small head);

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  Torticollis (wryneck);

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  Moderate to severe intellectual disability;

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  Seizures;

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  Autism spectrum disorder;

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  Loss of developmental milestones;

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  Generalized hypotonia (decreased muscle tone)

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  Global developmental delay;

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  Language impairment; and

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  Motor delay.

ICD-9: 318.1

ICD-10: F72

Individuals with SYNGAP1-related NSID continue to develop, progressing at their own pace. Unless their epilepsy is not well controlled, they do not regress or deteriorate and can always continue to learn.

OT, PT, and speech therapies to maximize developmental potential. Therapy is purely supportive.

Suggested MER for Evaluation:

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  Clinical history and examination that describes the diagnostic features of the impairment;

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  Genetic testing;

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  EEG results;

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  Brain MRI results; and

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  Neuropsychological testing documenting intellectual disability.

Suggested Listings for Evaluation:

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