Background:
Neurological disorders include a large group of conditions with genetic and phenotypic heterogeneity and often have overlapping clinical features, such as intellectual disability, seizures, microcephaly, motor disability, brain malformations (lissencephaly, molar tooth sign), vision loss, speech difficulties, and respiratory failure. Epilepsy is a common neurological disorder characterized by recurrent, unprovoked seizures. Childhood Epilepsy, also called Juvenile myoclonic epilepsy, is age specific type of epilepsy characterized by absence seizures, myoclonic seizures, and tonic-clonic seizures beginning between 5-16 years of age. This next-generation sequencing test is designed to detect mutations in the coding region of 48 genes associated with Childhood Epilepsy.
Reasons for Referral:
- Electroencephalogram results suspicious for epilepsy.
- Occurrence of seizures.
- Positive family history for epilepsy (targeted testing is available if familial mutation is known).
- Carrier testing.
Methodology:
Next generation sequencing will analyze the exons or coding regions of 48 Childhood Epilepsy-associated genes using Illumina NextSeq 500 technology. Samples are prepared using hybridization probes to enrich exonic regions. Promoter, intronic, etc. regions are not assessed on our assay, but may contain variants that impact gene function.
The 48 Childhood Epilepsy -associated genes are listed below: ADSL, CACNB4, CDKL5, CHRNA2, CHRNA4, CHRNB2, CLN3, CLN5, CLN6, CLN8, CNTNAP2, CSTB, CTSD, EFHC1, EPM2A, FOLR1, FOXG1, GABRA1, GABRG2, GAMT, GATM, GOSR2, GRIN2A, KCTD7, LGI1, MAGI2, MBD5, MECP2, MEF2C, MFSD8, NHLRC1, NRXN1, PNKP, POLG, PPT1, PRICKLE1, SCN1A, SCN1B, SCN2A, SLC2A1, SLC9A6, SYN1, TBC1D24, TCF4, TPP1, UBE3A, WDR45, ZEB2
Specimen Requirements:
- Blood: EDTA or ACD (Solution A or B):
- Adult: 5 mL
- Child: 5 mL
- Infant: 2-3 mL
- Saliva: 2 ORAgene Saliva Kits (OGR-500)
- Skin Fibroblast: Punch Biopsy, or 2 T-25 confluent flasks
- DNA: 3-4µg at a minimum of 50-100ng/µL (DNA must be extracted in a CLIA-certified laboratory or a laboratory meeting equivalent requirements as determined by the CAP and/or CMS)
For routine testing of blood, saliva and buccal swabs, KDL does NOT accept samples from patients within two (2) weeks of a packed cell/platelet transfusion or within four (4) weeks of a whole blood transfusion. For extraordinary circumstances, where testing must be performed outside of the above windows, please contact our lab.
A REQUISITION FORM MUST ACCOMPANY ALL SAMPLES. Please include detailed clinical information, including ethnicity, clinical history, and family history.
Test Performed (Days):
Weekly
Turn Around Time:
8 weeks
Shipment Sensitivity Requirements:
- Package and ship specimen to remain cold, but not frozen.
- Ship via overnight express, using the FedEx priority overnight label provided.
- Contact Client Services for shipping kits and instructions at (855) 535-1522.
References:
- Epilepsy Foundation
Additional Info: