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Test Code VLCAD KNWN VLCAD Known Mutation

Clinical System Name

VLCAD Known Mutation Analysis Request


VLCAD Known Variant Analysis

ACADVL Known Variant Analysis


This test involves targeted analysis for mutations previously identified through clinical testing of a family member or  research testing of the individual.  It can be used for carrier testing for at-risk relatives and prenatal testing for confirmed carriers. Mutations must be known. For full gene sequencing please see VLCAD Sequencing.


Very Long Chain Acyl-CoA Dehydrogenase Deficiency (VLCAD) is a treatable disorder of fatty acid metabolism caused by an inability to use very-long-chain fats for energy.  It is caused by mutations in the ACADVL gene.

Sample Requirements

Specimen: Whole blood, cord blood

Container(s): Lavender/EDTA, Yellow/ACD A or B

Preferred Vol: 3 mL

Minimum Vol: 1 mL


Note: Heparin samples (Green tops) are unacceptable.


Specimen: Extracted DNA

Minimum: 10µg

Note: DNA concentration minimum 50 µg/mL; 260/280 ratio 1.70-2.00


Specimen: Cultured cells

Acceptable:  Fibroblasts

Container(s): T-25 flasks

Preferred Vol: 2 flasks

Processing Instructions

Reject due to: Heparin

Spin: No

Aliquot: No

Temp: Refrigerate

Storage location: Molecular Genetics box in CPA refrigerator #2


Off-site collection: Refrigerate blood samples until ready to ship.  Transport all sample types at room temperature via overnight shipping.


Specimen Type Temperature Time
Cultured cells Room temp 3 days
Whole blood, extracted DNA Room temp 3-5 days
Whole blood, extracted DNA Refrigerated 7 days
Extracted DNA Frozen ok


Note: Whole blood samples > 7days may be submitted to be assessed by our lab for acceptability for testing.


STAT Performed TAT
Contact lab Monday - Friday 2-3 weeks

Follow-up testing requested based on Washington State Lab Newborn Screening Program referrals will be expedited.

Performing Laboratory

Seattle Children's Laboratory


Department:  Molecular Genetics Laboratory

Phone: 206-987-3872


Lab Client Services: 206-987-2617


Lab Genetic Counselors:

Reference Range

Interpretive report will be provided


Method: PCR + Sequencing


Limitations: This test is for targeted known mutation analysis only.  Mutations must be known.

CPT Codes

81403 (updated 2/2/16 by jconta)

Special Instructions

Please provide copies of proband reports when requesting known mutation analysis for cases NOT performed by Seattle Children's Lab.


Links to: VLCAD Genetics Home Reference Entry , Very Long-Chain Acyl-Coenzyme A Dehydrogenase Deficiency GeneReviews


Molecular Genetics

Clinical Utility

VLCAD is a treatable disorder of fatty acid metabolism caused by an inability to use very-long-chain fats for energy. Fatty acid metabolism occurs during prolonged fasting and/or periods of increased energy demands (fever, stress) when energy production relies increasingly on fat metabolism. Severe VLCAD can cause hypoketotic hypoglycemia, hepatomegaly, cardiomyopathy and arrhythmias, lethargy, and failure to thrive. The age of onset can be from early infancy to adulthood. Infants can present with hypoglycemia, liver disease, and cardiomyopathy, children who present outside of the newborn period present with hypoglycemia, enlarged liver, muscle weakness and most patients who show symptoms in teen years or adulthood have periods of muscle weakness and cramping with reddish-brown urine. Full gene sequencing will identify greater than 98% of mutations in affected individuals. Carrier testing for biological family members is available once mutations are known.

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