SYNGAP1 Syndrome

What is SYNGAP1 syndrome?

SYNGAP1 syndrome is a neurological disorder that is characterized by intellectual disability. Approximately one to two percent of all intellectual disability is the result of a mutated SYNGAP1 gene. 

What are the symptoms of SYNGAP1 syndrome?

Moderate to severe intellectual disability is the major symptom of SYNGAP1 syndrome. Other symptoms include:

• Developmental delays
  • Delays in picking up speech and motor skills, such as walking and sitting up
• Hypotonia
• Developmental regression
• Epilepsy
• Hyperactivity
• Autism spectrum disorder (in about half of all cases)

What causes SYNGAP1 syndrome?

A mutated SYNGAP1 gene results in this condition. If inherited, it is passed down in an autosomal dominant pattern, but it is typically a sporadic mutation. This gene is responsible for the SynGAP protein, which plays a role in regulating changes in synapses. When it is mutated, the protein is less active, leading to abnormalities in the nerve cells. These abnormalities then cause issues with memory and learning, along with other neurological issues associated with SYNGAP1 syndrome. 

How is SYNGAP1 syndrome diagnosed?

Doctors will investigate a SYNGAP1 syndrome diagnosis after noticing intellectual disability and epilepsy, two of the characteristic symptoms. This investigation typically begins soon after birth. To confirm a diagnosis and rule out other conditions, they will utilize genomic testing. 

What are the treatments for SYNGAP1 syndrome?

Treatment for this condition is symptomatic, and it may require a team of specialists. Intervention early in development leads to the best outcomes, with occupational, speech, and physical therapy being very helpful for most affected individuals. Rehabilitative and behavioral therapy may also be helpful. If epilepsy is present, anti-seizure medications are prescribed, although they are not always effective. Overall, treatment should be individualized to each patient and consist of year-round care. 

Where can I find out more about SYNGAP1 syndrome?

• • U.S. National Library of Medicine
  • NORD
  • SYNGAP Research Fund