Dravet syndrome (SCN1A) gene analysis

Dravet Syndrome (SCN1A) Gene Analysis 

Test Name: Dravet Syndrome (SCN1A) Gene Analysis

Test Overview:
Dravet Syndrome is a severe, early-onset epilepsy disorder commonly associated with pathogenic variants in the SCN1A gene, which encodes the Nav1.1 voltage-gated sodium channel involved in neuronal signaling. Genetic analysis can help confirm a suspected diagnosis and distinguish SCN1A-related epilepsy from other seizure disorders.

Indications:

• Suspected Dravet Syndrome or severe infantile-onset epilepsy
• Prolonged or recurrent febrile/afebrile seizures beginning in infancy
• Hemiclonic or generalized seizures
• Multiple seizure types or drug-resistant epilepsy
• Epilepsy with developmental slowing or regression
• Suspected SCN1A-related epilepsy or GEFS+

Sample:
Peripheral blood in an appropriate EDTA tube; other specimen types may be accepted depending on laboratory protocol.

Methodology:
SCN1A analysis may include DNA sequencing for small sequence variants and deletion/duplication analysis such as MLPA to identify copy-number changes. Current clinical practice may also use an epilepsy multigene panel that includes SCN1A.

Clinical Significance:
Detection of a pathogenic or likely pathogenic SCN1A variant can support the diagnosis of an SCN1A-related seizure disorder and assist clinicians with treatment planning, prognosis, and genetic counselling. Most Dravet-associated SCN1A variants arise de novo, although inheritance can occur.

Result Interpretation:
Results may be reported as Pathogenic, Likely Pathogenic, Variant of Uncertain Significance (VUS), Likely Benign, or Benign, depending on the variant identified. A negative result does not completely exclude Dravet Syndrome, as not all clinically diagnosed patients have an identifiable SCN1A variant.

Important Note:
Test results should be interpreted alongside the patient's clinical history, seizure characteristics, EEG findings, and specialist evaluation. Genetic counselling is recommended for appropriate interpretation and family-risk assessment.