The IVD gene gives your body instructions for breaking down leucine, one of the building blocks of protein in food. This gene helps your body clear one step in that process; when it does not work well, harmful acids can build up and cause isovaleric acidemia, which may lead to poor feeding, vomiting, unusual sleepiness, and a strong sweaty feet odor, especially during illness or fasting. Some people with harmful variants in the IVD gene also have repeated low energy episodes and may need ongoing care to support growth and development.
What is a gene?
A gene is a section of DNA that gives cells instructions for making molecules or managing processes in the body. Some genes provide the directions for producing proteins, which are the parts of cells that do much of the work. Others are mainly involved in controlling when certain processes happen, where they happen, and how active they are. Taken together, genes affect how the body grows and works, and they can also influence how you respond to food, stress, or medications. For a deeper look at this topic, you can find more in the LearnHub.
Overview
IVDGene function
What if the gene works
The IVD gene helps your body break down leucine, a protein building block from food. Its protein works in mitochondria, the cell’s energy centers, during energy production.
Risk
What if the gene does not work
More disruptive variants in the IVD gene can cause isovaleric acidemia, where the body cannot properly break down the amino acid leucine. Effects range from severe illness in newborns to milder later episodes, with vomiting, poor feeding, and low energy.
Treatment
What does that mean for your treatment
A pathogenic variant in the IVD gene can guide treatment toward long term leucine restriction, avoidance of fasting, and a sick day plan during illness. Many people also receive L-carnitine, glycine, or both to help clear harmful byproducts. If acute decompensation occurs, hospital care often includes IV glucose and temporarily stopping protein.
Conditions associated with IVD
Gene function
What if the gene works
Your body uses the IVD gene every day when it handles leucine, a building block from protein in food. Its protein helps cells process this nutrient in a careful sequence of steps. Understanding how the IVD gene helps break down leucine shows how your cells turn food into usable energy.
The IVD gene helps your cells process leucine, a building block from protein-rich foods. It carries out one step in the chain of reactions that turns leucine into smaller, usable parts.
As leucine is broken down, this gene helps release material your cells can use to make energy. This supports normal metabolism during growth, exercise, and time between meals.
Its protein moves leucine byproducts on to the next step, so breakdown stays organized. This work takes place in your cells' energy centers, where many fuel-making reactions happen.
What is a variant?
A genetic variant is a minor change in a gene’s DNA sequence. These changes are common and help shape normal differences among people, such as appearance, metabolism, or the way the body responds to environmental influences. Many variants do not have any noticeable effect and are simply part of natural genetic variation. Sometimes, though, a variant changes how a gene works more substantially and can contribute to or cause a genetic condition.
Genetic variants
What if the gene does not work
Many variants in the IVD gene reduce how well the IVD enzyme is made or folded, so cells break it down sooner or it works less efficiently. When looking at how IVD gene variants affect enzyme activity, milder changes may leave some function, while more severe variants can nearly abolish activity or stop the protein from being produced. This can shape whether isovaleric acidemia appears earlier with more noticeable features or remains milder.
How variants are linked to conditions
Pathogenic variants in both copies of the IVD gene cause isovaleric acidemia, an inherited condition that can lead to poor feeding, vomiting, unusual sleepiness, and episodes of illness, especially in infancy. The link between IVD gene variants and isovaleric acidemia is well established, although some people have a milder form found on newborn screening. People with one changed copy are usually healthy carriers.
A variant is not necessarily a diagnosis
Genetic variants are a routine part of human biology and are widely found across the general population. Most do not directly affect health and simply reflect natural human variation. In many genes, having a variant associated with a condition suggests a possible link rather than a certain diagnosis, particularly when several genes and environmental influences also play a role. In other situations, though, one well-characterized variant in a particular gene is enough to confirm a diagnosis.
Are there things that can increase or change my risk?
For people with harmful changes in both copies of the IVD gene, the main risk is set by the genetic change itself. In those living with this condition, illness, long gaps without food, and more protein than the body can handle can trigger sudden worsening. A child’s chance of having it is higher when both parents carry an IVD change.
Inheritance of IVD variants
Variants in the IVD gene are inherited in an autosomal recessive pattern. This means a child usually needs to inherit two nonworking copies of the IVD gene, one from each parent, to have IVD related isovaleric acidemia. Parents who each carry one variant are typically unaffected carriers, and with each pregnancy they have a 25% chance of having an affected child, a 50% chance of having a carrier child, and a 25% chance of having a child with no familial variant. In families asking how IVD gene variants are inherited, this pattern means boys and girls are affected equally.
What does my IVD result mean for my family?
For families with a disease-causing change in the IVD gene, close relatives may also be carriers, even if they feel completely well. Brothers and sisters could have the condition or be carriers, so the result can matter for siblings and future children in the family. For many, this means relatives may want to learn whether the same IVD change runs in the family.
Genetic information
Genetic testing
How you find out about variants
Genetic testing for IVD gene variants usually uses a blood or saliva sample to read the DNA sequence and look for changes linked to isovaleric acidemia. It can help confirm a diagnosis after newborn screening or symptoms, and it can also show whether someone carries an IVD variant that could be passed on in a family.
When should I consider getting a genetic test?
Genetic testing for the IVD gene may be considered if a baby has an abnormal newborn screening result for isovaleric acidemia, has symptoms of a metabolic crisis, or if there is a known family history. It can help confirm the diagnosis and show whether parents or other relatives are carriers.
A genetic result is only one part of your health story
Genetic test results can provide useful insight, yet how much they explain varies with the condition and the kind of variant involved. Over time, the way the body works is also shaped by factors such as age, environment, lifestyle, and medical history. For some conditions, especially those influenced by many genes, genetic information adds context rather than certainty and is best understood as part of the broader picture of care. In other situations, a genetic result may offer a clear answer. In areas such as medication response, genetic results can also help put individual experiences into perspective.
Pharmacogenetics
How variants shape your response to medicine
Genetic variation can affect how people respond to medicines. This helps explain why the same treatment may work well for one person, have less effect in another, or cause more side effects in someone else. Part of the reason is that inherited differences can change how the body breaks down, moves, or responds to a drug, which can influence both benefit and sensitivity.
What is Pharmacogenetics?
Pharmacogenetics looks at how genetic differences can affect the response to medications. It examines gene and drug patterns to better explain why the same treatment may work differently from one person to another. For many medicines, genes can influence how strongly a drug works or how the body processes it. This information can support more informed, individualized treatment decisions. For a more detailed look at this topic, you can learn more in the LearnHub.
Drugs influenced by the IVD gene
When should I seek medical advice?
There is not yet a broadly confirmed role for this gene in predicting medicine response. If you have concerns about side effects, a new prescription, or changes to your usual treatment, talk with your doctor or pharmacist.