SYNGAP1 related intellectual disability (SYNGAP1-related intellectual disability) - Gen SYNGAP1            

Intellectual disability related to SYNGAP1 is a neurological disorder characterized by mental retardation ranging from moderate to severe and that is evident in early childhood. The first signs usually include delayed language development and motor, such as sitting, getting up and walking skills. Many people will manifest hypotonia, developmental regression, episodes of epilepsy, hyperactivity and autism spectrum disorders. Almost all people with intellectual disabilities related to SYNGAP1 develop epilepsy, and about half have an autism spectrum disorder.

This process is due to mutations in the SYNGAP1 (GTPase activating protein Ras synaptic 1) gene, located on the short arm of chromosome 6 (6p21.3). This gene encodes the protein SynGAP, which plays an important role in brain neurons. This SynGAP protein is in the synapse, which is performed communication from cell to cell. SynGAP helps regulate adaptations or synapses and promotes proper brain connections. The function of the protein is particularly important during a critical period in early brain development affecting future cognitive ability.

They have been described at least 40 mutations in the gene SYNGAP1 in people with learning disabilities related SYNGAP1. The identified mutations inhibit the synthesis of functional SynGAP from a copy of the gene, which results in a reduction in activity of the protein in cells. Studies show that a reduction in activity SynGAP can have multiple effects on nerve cells. The changes brought about by a reduction in activity SynGAP disrupt synaptic adaptations in the brain that underlie learning and memory, leading to cognitive impairment and other neurological problems characteristic of intellectual disability related to SYNGAP1.

This process is inherited as an autosomal dominant, which means that a copy of the altered gene in each cell is sufficient to express the disease. Almost all cases are due to new mutations in the gene and occur in people with no history of disease in your family. In at least one case, an affected person has inherited the mutation from an affected parent.

Tests performed in IVAMI: in IVAMI perform detection of mutations associated with mental retardation related SYNGAP1 by the complete PCR amplification of exons SYNGAP1 gene, and subsequent sequencing.

Samples recommended: EDTA blood collected for separation of blood leukocytes, or impregnated sample card with dried blood (IVAMI may mail the card to deposit the blood sample).