The ABAT gene helps break down GABA, a brain chemical that carries calming signals between nerve cells. When a person has pathogenic variants in both copies of this gene, GABA can build up and cause a rare inherited condition with developmental delay, low muscle tone, seizures, and movement differences. This gene plays an important role in keeping brain signaling balanced.
What is a gene?
Genes are stretches of DNA that carry instructions cells use to make molecules or control activities in the body. Some genes provide the directions for producing proteins, the parts of cells that do much of the work. Others mainly regulate when certain processes happen, where they happen, and how strongly they occur. Together, genes affect how the body develops and functions, and they can shape how you respond to food, stress, or medications. You can find more on this topic in the LearnHub.
Overview
ABATGene function
What if the gene works
The ABAT gene helps break down GABA, a chemical messenger that calms nerve cells. This supports balanced brain signaling and helps mitochondria, the cell's energy makers, work normally.
Risk
What if the gene does not work
More severe variants in the ABAT gene can cause GABA transaminase deficiency, with developmental delay, low muscle tone, seizures, and movement problems. Milder variants may leave some enzyme activity, which can affect when symptoms appear and how severe they are.
Treatment
What does that mean for your treatment
No ABAT-specific treatment or management approach is currently established. The ABAT gene is a known drug target because vigabatrin blocks this enzyme, so ABAT-related pathways are being studied in epilepsy, but this is not a gene-directed treatment for ABAT deficiency.
Conditions associated with ABAT
Gene function
What if the gene works
Your brain and many other tissues need a steady way to clear used chemical signals. The ABAT gene helps by making an enzyme that breaks down GABA, a calming chemical messenger in the nervous system. This everyday process shows how the ABAT gene helps break down GABA in the body and supports normal cell activity.
The ABAT gene makes an enzyme that breaks down GABA after it has carried a nerve cell message. This helps keep GABA at a balanced level from one signal to the next.
By clearing GABA in a controlled way, the ABAT gene supports the normal rhythm of nerve signaling. This helps brain cells communicate with the right amount of calming input.
After GABA is broken down, some of its parts move into mitochondria (the cell’s energy centers) for routine energy use. This connects chemical signaling with everyday cell fuel production.
What is a variant?
A genetic variant is a minor change in the DNA sequence of a gene. These changes are common and help shape normal human diversity, including differences in appearance, metabolism, and how the body responds to environmental influences. Many variants do not have any noticeable effect and simply represent natural genetic variation. In some cases, though, a variant can change how a gene functions more substantially and may contribute to or cause a genetic condition.
Genetic variants
What if the gene does not work
ABAT gene variants can affect protein function by altering the enzyme’s shape, stability, cell targeting, or ability to bind its helper molecule, which can leave it partly active or nearly inactive. Some variants are milder and preserve residual activity, while more disruptive variants can sharply reduce enzyme function or prevent the protein from working. In GABA transaminase deficiency, this functional range can influence how early features appear and how pronounced they are.
How variants are linked to conditions
Pathogenic variants in both copies of the ABAT gene cause ABAT deficiency, a rare inherited condition that often starts in infancy. This ABAT gene condition is linked to developmental delay, low muscle tone, seizures, and changes in movement or behavior. Some children also have feeding difficulties or vision problems.
A variant is not necessarily a diagnosis
Genetic variants are a normal feature of human biology and are common among people in general. Most do not directly affect health and simply reflect natural human diversity. For many genes, carrying a variant associated with a condition points to a possible link rather than a definite diagnosis, especially when several genes and environmental factors are involved. In some situations, though, a single well-characterized variant in a specific gene is enough to confirm a diagnosis.
Are there things that can increase or change my risk?
There is not yet broadly confirmed evidence on specific factors that increase or reduce health risk related to the ABAT gene. For people who carry disease-causing changes in both copies of ABAT, the condition is mainly driven by the genetic change itself, so day-to-day habits are not known to meaningfully change whether it develops.
Inheritance of ABAT variants
ABAT-related conditions follow an autosomal recessive inheritance pattern. In practical terms, ABAT gene inheritance usually means a child is affected only when they inherit one changed copy of the ABAT gene from each parent. 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 without the familial variant. Because the ABAT gene is on chromosome 16, this pattern is the same for males and females.
What does my ABAT result mean for my family?
For families with an ABAT-related condition, this usually means parents are healthy carriers, and brothers or sisters may also be affected or may be carriers. Close relatives, such as siblings of the parents, can sometimes be carriers too, so the result may matter beyond one person. Family testing can help clarify who else in the family may carry the same ABAT change.
Genetic information
Genetic testing
How you find out about variants
Genetic testing for ABAT gene variants usually uses a blood sample or cheek swab to read the ABAT gene and look for changes in its DNA code. It can show whether you carry a benign variant, a variant linked to a condition related to the ABAT gene, or a variant that needs interpretation alongside symptoms and family history.
When should I consider getting a genetic test?
Consider ABAT genetic testing when a child has unexplained early seizures, major developmental delay, very low muscle tone, or unusual movements, especially with a family history of a similar condition. Testing can help confirm whether ABAT is the cause.
A genetic result is only one part of your health story
A genetic result can provide useful insight, but the amount it reveals depends on the condition and the specific type of variant. Over time, many factors, including lifestyle, environment, age, and medical history, influence how the body functions. For some conditions, particularly those shaped by many genes, genetic information offers context rather than certainty and makes the most sense when considered with other parts of care. In other situations, a genetic result can give a clear answer. In areas like medication response, genetic results may help put personal experiences in context.
Pharmacogenetics
How variants shape your response to medicine
Genetic variation can affect how your body responds to medicines. This helps explain why the same medication may work well for one person, have less effect in another, or cause more side effects in someone else, because the body can absorb, break down, or respond to drugs differently. These differences are common and can influence both how well a treatment works and how sensitive a person is to it.
What is Pharmacogenetics?
Pharmacogenetics examines how differences in a person’s genes affect medication response. It looks at gene-drug patterns to help explain why the same treatment can work differently from one person to another. For many medicines, genes influence how strongly a drug works or how the body handles it. This information can support treatment decisions that are more informed and more individualized. You can read more about this topic in the LearnHub.
Drugs influenced by the ABAT gene
When should I seek medical advice?
There is not yet a broadly confirmed role for this gene in guiding medication choices, so general questions about medicines or side effects are best discussed with your doctor. ABAT is the body target of vigabatrin, a seizure medicine, so specialists may sometimes consider it in research or rare epilepsy care, but this is not part of routine prescribing guidance.
History
Research on the ABAT gene grew out of mid 20th century work on brain chemistry, when scientists were mapping the pathways involved in gamma aminobutyric acid, or GABA. Initially understood only through enzyme activity, later recognized as tied to a specific gene, ABAT became clinically important when rare inherited deficiency was described in children with developmental and neurologic features. From these first observations, research expanded steadily as laboratory methods improved and the gene could be mapped and sequenced more precisely. By the late 20th and early 21st centuries, ABAT testing had become part of the workup for some unexplained neurodevelopmental conditions. These historical steps shaped today’s understanding of ABAT as a rare but well established gene in medical genetics.