SCN2A is one of top candidate genes
strongly associated with autism. Over the last years, whole exome sequencing has successfully identified over 100 genes associated with autism spectrum disorders - and the gene SCN2A has one of the strongest evidence for association with autism. Very often, intellectual disability
is also observed.
SCN2A has also been associated with seizures
in the first year of life, ranging from benign infantile familial seizures without obvious neuropsychiatric symptom to epileptic encephalopathy with long-term neurodevelopmental delay.
Apart from autism/intellectual disability and/or epilepsy, several comorbidities
are observed in patients with SCN2A mutations:
Autonomic dysfunction
Cerebral palsy (spasticity, hypotonia)
Cortical Vision Impairment (CVI)
Gastro-intestinal dysfunction (reflux, constipation)
Movement disorders (chorea, ataxia, dystonia)
Neuropathic pain
Sleep disorders
Speech and language deficit
Urology problems
Should an undiagnosed patient show one or several of the disorders mentioned above, SCN2A Europe strongly recommends genetic testing, for different reasons:
SCN2A mutations are twofold - sodium channels can either be over-excited (Gain-of-Function, GoF) or be under-excited (Loss-of-Function, LoF) - disorders will differ but, more important, also the drugs to be used (e.g. no sodium blockers for LoF cases, in general)
Knowing the source of the problem and its mechanisms will help in the decision of the therapeutic measures to be taken
In the next few years, clinical tests of certain drugs will start - the more SCN2A cases are registered, the better towards approval of new drugs
SCN2A Europe is aware of the different hurdles to get a diagnosis. Under 'Resources' you will find supportive information which could help you in this journey.