Epilepsy: Autosomal Dominant Nocturnal Frontal Lobe Epilepsy, Type 4 via the CHRNA2 Gene
Summary and Pricing 
Test Method
Sequencing and CNV Detection via NextGen Sequencing using PG-Select Capture ProbesTest Code | Test Copy Genes | Test CPT Code | Gene CPT Codes Copy CPT Code | Base Price | |
---|---|---|---|---|---|
7945 | CHRNA2 | 81479 | 81479,81479 | $990 | Order Options and Pricing |
Pricing Comments
This test is also offered via our exome backbone with CNV detection (click here). The exome-based test may be higher priced, but permits reflex to the entire exome or to any other set of clinically relevant genes.
An additional 25% charge will be applied to STAT orders. STAT orders are prioritized throughout the testing process.
Testing run on PG-Select capture probes does not include exome-wide CNV analysis. Reflex is available to PGxome or an exome-based panel, or you can use this gene list to create a custom panel (click here).
Click here for costs to reflex to whole PGxome.
Turnaround Time
3 weeks on average for standard orders or 2 weeks on average for STAT orders.
Please note: Once the testing process begins, an Estimated Report Date (ERD) range will be displayed in the portal. This is the most accurate prediction of when your report will be complete and may differ from the average TAT published on our website. About 85% of our tests will be reported within or before the ERD range. We will notify you of significant delays or holds which will impact the ERD. Learn more about turnaround times here.
Targeted Testing
For ordering sequencing of targeted known variants, go to our Targeted Variants page.
Clinical Features and Genetics 
Clinical Features
Autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE) is a childhood onset focal epilepsy characterized by seizures that occur during non-REM sleep. Seizures in ADNFLE patients can present as repetitive limb movements, sudden awakening, dystonic posturing, sleep walking, or elevation of the body or head with fear. Seizures are brief, lasting from 5 seconds to 5 minutes, and often patients maintain consciousness throughout the attack. Frontal origin of ADNFLE seizures is revealed by EEG recordings. ADNFLE associated seizures are often managed with low doses of antiepileptic drugs (AEDs). ADNFLE is not generally associated with severe cognitive deficits or psychiatric problems, however, studies suggests that ADNFLE may have wider neurological phenotypes (Aridon et al. 2006. PubMed ID: 16826524; Steinlein et al. 2012. PubMed ID: 22036597; Wood et al. 2010. PubMed ID: 20189461; Bennett et al. 2017. PubMed ID: 28717674).
Genetics
ADNFLE is inherited in an autosomal dominant manner and can be caused by pathogenic variants in the CHRNA2 gene (Aridon et al. 2006. PubMed ID: 16826524; Trivisano et al. 2015. PubMed ID: 25847220). CHRNA2 encodes neuronally expressed subunit 2 of the nicotinic cholinergic receptor (nAChR) which is a neurotransmitter-gated ion channel that has been fine-tuned through evolution to transduce a chemical signal into an electrical signal. The ADNFLE-associated CHRNA2 pathogenic variants are missense and nonsense. No large deletions or duplications have been reported (Human Gene Mutation Database).
Clinical Sensitivity - Sequencing with CNV PG-Select
In a cohort of 77 unrelated Autosomal dominant nocturnal frontal lobe epilepsy patients, one had a pathogenic variant in CHRNA2 (Conti et al. 2015. PubMed ID: 25770198).
Testing Strategy
This test provides full coverage of all coding exons of the CHRNA2 gene, plus ~10 bases of flanking noncoding DNA. We define full coverage as >20X NGS reads or Sanger sequencing.
Indications for Test
CHRNA2 sequencing is recommended for patients who are suspected to have autosomal dominant nocturnal frontal lobe epilepsy.
CHRNA2 sequencing is recommended for patients who are suspected to have autosomal dominant nocturnal frontal lobe epilepsy.
Gene
Official Gene Symbol | OMIM ID |
---|---|
CHRNA2 | 118502 |
Inheritance | Abbreviation |
---|---|
Autosomal Dominant | AD |
Autosomal Recessive | AR |
X-Linked | XL |
Mitochondrial | MT |
Disease
Name | Inheritance | OMIM ID |
---|---|---|
Epilepsy, Nocturnal Frontal Lobe, Type 4 | AD | 610353 |
Citations 
Ordering/Specimens 
Ordering Options
We offer several options when ordering sequencing tests. For more information on these options, see our Ordering Instructions page. To view available options, click on the Order Options button within the test description.
myPrevent - Online Ordering
- The test can be added to your online orders in the Summary and Pricing section.
- Once the test has been added log in to myPrevent to fill out an online requisition form.
- PGnome sequencing panels can be ordered via the myPrevent portal only at this time.
Requisition Form
- A completed requisition form must accompany all specimens.
- Billing information along with specimen and shipping instructions are within the requisition form.
- All testing must be ordered by a qualified healthcare provider.
For Requisition Forms, visit our Forms page
Specimen Types
Specimen Requirements and Shipping Details
ORDER OPTIONS
View Ordering Instructions1) Select Test Type
2) Select Additional Test Options
STAT and Prenatal Test Options are not available with Patient Plus.
No Additional Test Options are available for this test.