Comprehensive Epilepsy + mtDNA
|TAT (TURNAROUND TIME)||2 - 4 weeks|
|CPT CODE||81460, 81465, 81405 x2, 81406 x3, 81407 x1, 81479|
|RECOMMENDED MNG KITS||
Epilepsy is a chronic seizure disorder or group of disorders (more than one seizure within 6 months) characterized by seizures that usually recur unpredictably in the absence of a consistent provoking factor. They can be classified into the following categories: Partial seizures – Cortical origin (Affecting one hemisphere), Generalized seizures – Subcortical Origin (Affecting both hemispheres), Unclassified Seizures – Neonatal, and Status Epilepticus – Seizures occur repeatedly with no recovery of consciousness between attacks.
Most epilepsy syndromes are genetically heterogeneous; pathogenic variants in different genes cause the same syndrome in different individuals or families, and only a fraction of the potential genetic causes have so far been identified. Genetic assessment is enhanced when clinical information is available. Although a positive test result can confirm or suggest that an individual has a specific syndrome, a negative test result might be uninformative. For instance, fewer than one in five individuals with autosomal dominant nocturnal frontal lobe epilepsy have a pathogenic variant in any of the genes currently associated with that disorder. Conversely, in syndromes with incomplete penetrance and variable expressivity, a positive test result in an unaffected family member does not necessarily mean that the individual will develop epilepsy in the future, nor can it predict the specific phenotype if the individual does. An important example of this problem is genetic epilepsy with febrile seizures plus (GEFS+), in which some family members with a SCN1A variant remain unaffected, and phenotypes in affected family members vary from simple age-limited febrile seizures to severe epileptic encephalopathies (PMID:24733164).
|Acceptable Sample Types||
|Sample Preparation:||(1) Blood specimens: Draw blood in an EDTA tube. Preferred volume: 4 milliliters (adults and pediatrics), Minimum volume: 2 milliliters; (2) DNA extracted from leukocytes, muscle, or fibroblasts: Preferred quantity: 4 micrograms, Minimum quantity: 3 micrograms (Genomic DNA should be eluted in sterile Dnase/Rnase free water or TE. The A260:A280 ratio should be 1.8-2.0.); (3) 2 T-25 flasks of fibroblasts; (4) 50-75 milligrams muscle snap frozen in liquid nitrogen and maintained at -80°Celsius or below. (5) Skin biopsy (Fibroblasts will be cultured from skin specimen for genetic testing): Skin biopsy may be taken from the inner forearm with a sterile skin punch (2-5 millimeters) or at incision site of muscle biopsy. Site is sterilized with alcohol swabs only (other reagents will inhibit cell isolation/growth). Biopsy site may be anaesthetized with 2% lidocaine with epinephrine. Depth of punch is 2mm. Transfer skin biopsy into 15 milliliter conical tube filled with sterile culture media. (6) Buccal cells.|
|Shipping Condition:||MNG SmartKits are available for free shipping of specimens. Please see our website for details. If you are not using a MNG SmartKit: (1) Blood specimens should be shipped in a secure container at room temperature. (2) Extracted DNA should be shipped priority overnight at ambient temperature. (3) T-25 flasks containing fibroblasts should be shipped in an insulated container at room temperature. Flasks should be completely filled with media and cells should be ~90% confluent. Fibroblast samples must be certified free from Mycoplasma. MNG is able to perform this service for a small charge (See TC05). (4) Muscle samples should be shipped frozen in an insulated container with 5-7 lbs dry ice. (5) Buccal cells should be shipped in a secure container at room temperature. (6) Skin Biopsy: Conical containing the skin specimen should be shipped in a secure container with cold pack (DO NOT FREEZE). All samples should be shipped overnight at the proper temperature for receipt by our lab Monday thru Saturday (No Sunday or holiday deliveries accepted).|