SYNGAP1-Related Intellectual Disability Syndrome

SRID syndrome is a neurodegenerative disorder characterized by moderate to severe mental disability and manifest in early childhood. The first feature of this syndrome is impairment in the development of speech and motor skills such as sitting, standing and walking [1] (Figure 1).

Many people with a SRID syndrome have muscular weakness (hypotonia), which impairs the development of motor skills. Some sufferers also lose the skills they have already learned (regression). Other features of the SRID syndrome include: frequent seizures (epilepsy), hyperactivity and autism spectrum disorders characterized by communication disruption and social interactions. Almost all people with SRID syndrome have epilepsy and almost half of them have autism spectrum disorders [2] (Figure 2).

The SRID syndrome is caused by the mutation of the SYNGAP1 gene, which is based on the short arm of chromosome 6, which is positioned as 6p21.32. The protein produced from this gene is known as SynGAP, which plays an important role in neurons in the brain. SynGAP protein is found in connections between nerve cells (synapses) and helps regulate changes in synapses that are essential for learning and memory [3] (Figure 3).

The mutation in the SYNGAP1 gene results in incomplete production or a decrease in the activity of the SynGAP protein. Studies have shown that reducing the activity of SynGAP protein can have several effects on neurons, including synapses stimulation for early development. Abnormalities due to synaptic changes in the brain cause impairment in learning, memory and behavior that are characteristic of SRID syndrome [4] (Figure 4).

SRID syndrome follows the dominant autosomal inheritance pattern. Therefore, to produce this syndrome, a copy of the mutated gene SYNGAP1 (parent or parent) is required and the chance of having a child with this syndrome in the dominant autosomal state is 50% for each possible pregnancy. It is worth noting that almost all cases of SRID syndrome are caused by new gene mutations and no family history [5] (Figure 5).

SRID syndrome is a relatively common form of cognitive impairment. It is estimated that the syndrome accounts for about 1-2% of intellectual disability cases [6].

The SRID syndrome is diagnosed based on the clinical and clinical findings of the patients and some pathological examinations.The most accurate method for detecting this syndrome is the molecular genetic testing of the SYNGAP1 gene to investigate the presence of possible mutations [6].

The SRID syndrome treatment and management strategy is symptomatic and supportive. Treatment may be done by a team of experts, including a neurologist, orthopedic specialist and other healthcare professionals. There is no standard treatment for this syndrome and all clinical measures are needed to reduce the suffering of the infected person. Genetic counseling is also a special place for all parents who want a healthy baby [7].

As noted, cold syndrome is a neuro genetic disorder that disrupts the thinking and thinking ability of the affected person. To date, only one gene has been identified for this syndrome, but researchers are trying to discover other genes in inducing this syndrome.

None.

No conflict of interest.

1. Aceti M, Creson TK, Vaissiere T, Rojas C, Huang WC, et al. (2015) Syngap1 haploinsufficiency damages a postnatal critical period of pyramidal cell structural maturation linked to cortical circuit assembly. Biol Psychiatry 77(9): 805-815.
2. Clement JP, Aceti M, Creson TK, Ozkan ED, Shi Y, et al. (2012) Pathogenic SYNGAP1 mutations impair cognitive development by disrupting maturation of dendritic spine synapses. Cell 151(4): 709-723.
3. Clement JP, Ozkan ED, Aceti M, Miller CA, Rumbaugh G (2013) SYNGAP1 links the maturation rate of excitatory synapses to the duration of critical-period synaptic plasticity. J Neurosci 33(25): 10447-10452.
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7. Wang CC, Held RG, Hall BJ (2013) SynGAP regulates protein synthesis and homeostatic synaptic plasticity in developing cortical networks. PLoS One 8(12): e83941.