Calcium Channel Alpha-1 Subunit (CACNA1S) Genetic Mutation Analysis
This test checks for specific genetic changes in the CACNA1S gene, which may be linked to certain muscle or nerve disorders.
Identifying mutations in the CACNA1S gene can help diagnose or assess risk for rare genetic conditions.
Key facts at a glance
- LOINC
- 57918-5
- Short code
- CACNA1S-SCN4A
- Synonyms
- CACNA1S+SCN4A gene Mut Anl Bld/T
- Category
- chemistry
- Sample
- whole-blood
- Container
- EDTA (purple-top) blood collection tube for whole blood; sterile container for tissue specimens
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- ≥ 0 years
- Method
- molgen
- CPT
- 81403
- SNOMED
- 760897007
- Specimen volume
- 3-5 mL whole blood in EDTA tube; minimum 1 mL for pediatric samples; 5-10 mg tissue for tissue specimens
- Stability
- Whole blood: stable for 7 days at 2-8°C; ambient (15-25°C) for 48 hours; do not freeze. DNA extracted from blood: stable for years at -20°C or -80°C. Tissue: stable for 24 hours at 2-8°C; freeze at -80°C for longer storage.
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 336–720 hours
- Order
- routine
Why This Test Might Be Ordered
Your healthcare provider may recommend this test if you have symptoms of a muscle or nerve disorder, a family history of related genetic conditions, or if genetic testing is part of a broader diagnostic evaluation for unexplained health issues.
What to Expect Before the Test
No special preparation is typically needed. If blood is drawn, you may have a slight bruise or discomfort at the site, but it usually resolves quickly. If saliva or another specimen is used, you may need to avoid eating/drinking for a short time before collection.
What the Results Mean
Results can be positive (indicating a mutation) or negative (no mutation detected). Positive results may require further evaluation by a genetic counselor or specialist to understand implications for your health and family members.
Common Conditions Linked to CACNA1S Mutations
Mutations in this gene may be associated with conditions affecting muscle function, such as myotonic dystrophy or certain types of epilepsy, though symptoms vary widely.
Reference range
No mutations detected in the CACNA1S and SCN4A genes analyzed (Nominal result: Negative for pathogenic variants). Reference interpretation is based on the presence or absence of known disease-associated mutations; a negative result does not exclude mutations in untested regions or genes.N/A
No fasting required. Patients should provide informed consent for genetic testing. A detailed family history and clinical phenotype information should accompany the sample to aid in result interpretation. Genetic counseling is recommended before and after testing.
Frequently asked questions
What does a positive result mean?
Will this test affect my insurance or ability to work?
Can I get this test if I don’t have symptoms?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy