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Diagnostic Services

Genetics Lab


Very Long Chain Acyl-CoA Dehydrogenase Deficiency DNA Sequencing

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.

Test Name: VLCAD DNA Sequencing
Test Code:
Test Description:
Polymerase Chain Reaction (PCR) followed by sequence analysis of the entire coding region (20 exons) of the ACADVL gene.
This test is used to provide additional information regarding diagnosed patients or as a secondary confirmation of diagnosis since biochemical testing can be ambiguous at times. Sequencing can also be used for carrier testing.
Related Tests: Acylcarnitine Profile, Blood  
For confirmation of newborn screening results, evaluating patients with episodes of lethargy or vomiting suggestive of a metabolic disorder and for follow-up of known patients for assessment of management.

Clinical Links: VLCAD OMIM Entry
VLCAD Genetics Home Reference Entry
Mon - Fri
Turnaround Time:
2-3 weeks
PCR followed by Sequencing
Reference Range:
Interpretive report will be provided
Consent Form:
Sample Requirements: Type
Whole blood: 1-3 mL in EDTA (purple top) or ACD (yellow top).
DNA: 5 micrograms extracted DNA.

Do not spin. Keep at room temperature

Room temperature via overnight shipping. Blood samples must be processed within 3 days of collection
Samples Received:
Monday - Friday 8am - 5pm PST
Special Considerations:
Please e-mail Lab Client Services ( or call at 206-987-2617 with any billing questions
CPT Code:
Please e-mail Lab Client Services ( or call at 206-987-2617 with any billing questions