National Center for Advancing and Translational Sciences Genetic and Rare Diseases Information Center, a program of the National Center for Advancing and Translational Sciences

VLCAD deficiency



My husband and I were recently told we are carriers, and our first baby girl died at about 40 hrs old from VLCAD. I am now pregnant with another little girl and we worry about this baby having VLCAD. What are the chances that she comes out and has the condition and dies? And if she does have it, is there any treatment I can do before she's born? Can she survive having the mutated gene and live a healthy life?


Is VLCAD deficiency inherited?

VLCAD deficiency is inherited in an autosomal recessive manner.[1] This means that to be affected, a person must have a mutation in both copies of the responsible gene in each cell. The parents of an affected person usually each carry one mutated copy of the gene and are referred to as carriers. Carriers typically do not show signs or symptoms of the condition. When two carriers of an autosomal recessive condition have children, each child has a 25% (1 in 4) risk to have the condition, a 50% (1 in 2) risk to be a carrier like each of the parents, and a 25% chance to not have the condition and not be a carrier.
 
Last updated: 6/28/2015

If both parents are carriers of VLCAD deficiency, what are the chances of having an affected child?

VLCAD deficiency is inherited in an autosomal recessive manner.[1] This means that when both parents are carriers, each child has a 25% (1 in 4) risk to have the condition. This also means that each child has a 75% (3 in 4) risk to be unaffected.
Last updated: 6/29/2015

Is it possible to find out if my child will have VLCAD deficiency before birth?

Yes, it is often possible to find out if a child will have VLCAD deficiency before birth. Genetic testing is the preferred method of prenatal diagnosis; however, it is only an option If the disease-causing mutation(s) in the family are known (i.e. if an affected person or the carriers in the family have had genetic testing). This testing can be performed either by chorionic villus sampling (CVS) at 10-13 weeks gestation, or by amniocentesis (typically performed at 16 weeks or later). Samples taken from either of these tests can be analyzed for the presence of the mutation(s) known to occur in the family.[1]

If genetic testing is not an option, enzyme testing can often be performed on a sample collected via amniocentesis. This test measures the enzyme that is responsible for breaking down very long-chain fatty acids, which is low in people with VLCAD deficiency.[1]

Individuals who are interested in learning more about prenatal diagnosis for VLCAD deficiency should speak with a genetics professional.
Last updated: 6/29/2015

Is there treatment during pregnancy for a baby affected with VLCAD deficiency?

We are not aware of any treatments during pregnancy for a baby that is known to be affected with VLCAD deficiency, or at increased risk for having VLCAD deficiency. However, finding out the genetic status of a baby known to be at increased risk may help parents prepare for the birth of an affected infant. For example, if life-threatening heart problems are expected, it may be beneficial to consult with a pediatric cardiologist or other specialists in order to prepare for prompt and appropriate treatment as soon as the baby is born.
Last updated: 6/29/2015

What is the long-term outlook for people with VLCAD deficiency?

The long-term outlook (prognosis) for people with VLCAD deficiency is hard to predict and can vary based on the severity of the condition.

For people with the severe, early-onset form, cardiomyopathy and arrhythmias can be lethal. However, heart function can be improved with early treatment and specific diet modifications. Normal intellectual outcome has been reported in people with this form.[1]

For people with the hepatic (liver) or hypoketotic hypoglycemic form, hypoketotic hypoglycemia can cause a loss of consciousness or seizures.[1]

People with the later-onset episodic myopathic form may only have muscle-related symptoms. Some people with this form may not be diagnosed until adulthood. Since the later-onset form can have vague or intermittent symptoms, it is possible that some people may have no symptoms during their lifetime.[1]
Last updated: 6/29/2015

How can I find a genetics professional in my area?

To find a medical professional who specializes in genetics, you can ask your doctor for a referral or you can search for one yourself. Online directories are provided by the American College of Medical Genetics and the National Society of Genetic Counselors. If you need additional help, contact a GARD Information Specialist. You can also learn more about genetic consultations from Genetics Home Reference.
Last updated: 12/6/2017

We hope this information is helpful. We strongly recommend you discuss this information with your doctor. If you still have questions, please contact us.

Warm regards,
GARD Information Specialist

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  1. Nancy D Leslie, MD, C Alexander Valencia, PhD, Arnold W Strauss, MD, Jessica Connor, MS, and Kejian Zhang, MD, MBA. Very Long-Chain Acyl-Coenzyme A Dehydrogenase Deficiency. GeneReviews. September 2014; http://www.ncbi.nlm.nih.gov/books/NBK6816/.