What are FAOD?
Gene mutations impair enzyme activity1
Fatty acid oxidation disorders (FAOD) are a group of ultrarare genetic conditions in which an enzyme that ordinarily breaks down fat is either at a very low level or not functioning normally.
In healthy people, the body uses glucose (sugar) for energy. Once the body has used up all available glucose, it uses fatty acids as an energy source.
In people with FAOD, the enzyme responsible for breaking down fatty acids is either at a very low level or not functioning normally. Without being able to break down fatty acids, the body must find other energy sources, such as glucose. This causes the signs and symptoms of FAOD.
FAOD affect 1 in 4600 people in the United States2,3
Long-chain FAOD (LC-FAOD) are a specific group of FAOD. The most common types of LC-FAOD are
- Very long–chain acyl-coenzyme A dehydrogenase (VLCAD) deficiency
- Long-chain 3-hydroxyacyl-coenzyme A dehydrogenase (LCHAD) deficiency
- Trifunctional protein (TFP) deficiency
- Carnitine palmitoyltransferase I and II (CPT I and II) deficiency
Life with FAOD: Tasia’s Story
Other kinds of FAOD4
- Carnitine transport defect (primary carnitine deficiency)
- Carnitine-acylcarnitine translocase (CACT) deficiency
- 2,4 dienoyl-CoA reductase deficiency
- Medium-chain acyl-CoA dehydrogenase (MCAD) deficiency
- Short-chain acyl-CoA dehydrogenase (SCAD) deficiency
- 3-hydroxyacyl-CoA dehydrogenase (HADH) deficiency; also known as short-chain l-3-hydroxyacyl-CoA dehydrogenase (SCHAD) deficiency
- Electron transfer flavoprotein (ETF) dehydrogenase deficiency; also known as glutaric aciduria II (GAII) or multiple acyl-CoA dehydrogenase (MAD) deficiency
- 3-hydroxy-3methylglutaryl-CoA lyase (HMG) deficiency
- Unclassified FAOD
CoA, coenzyme A.
FAOD are inherited in an autosomal recessive manner5
Autosomal recessive describes the way the genes are passed down. Everyone carries some recessive genes. If a person has only one copy of a recessive gene, they generally do not develop the disease associated with the recessive gene. However, if a person has two copies of an abnormal recessive gene, an autosomal recessive disease can develop.
These recessive genes are inherited. For a person to inherit FAOD, they must receive one abnormal gene from each parent.
Signs & symptoms4,6-8
Most people are now diagnosed with FAOD after an abnormal newborn screening.
Starting in 1999, newborn screening gradually expanded by state to include testing for FAOD. People born before 1999 can be evaluated for suspected FAOD symptoms, and they may need to take a blood test.
Talk to your doctor if you suspect that you may have FAOD.
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