The GLS gene gives your body instructions to make an enzyme that turns glutamine, a nutrient building block, into glutamate, a chemical nerve cells use for signaling and fuel. Every cell in your body uses this gene to help manage energy, and it is especially important in the brain. If the gene does not work well, brain signaling and cell energy balance can be disrupted. Rare severe inherited variants in the GLS gene are linked to developmental delay, seizures, and other neurologic symptoms.
What is a gene?
A gene is a stretch of DNA that holds instructions your cells use to make molecules or regulate activities in the body. Some genes carry the directions for making proteins, which are the parts of cells that do the work. Other genes mainly help determine when certain processes happen, where they happen, and how strongly they are carried out. Together, genes affect how the body develops and works, and they can influence how you respond to food, stress, or medicines. If you want to look into this subject in more detail, you can read more in the LearnHub.
Overview
GLSGene function
What if the gene works
The GLS gene helps cells turn glutamine into glutamate. This supports energy production and, in the brain, helps make signals between nerve cells.
Risk
What if the gene does not work
Changes in the GLS gene can cause a rare condition with developmental delay, balance problems, and sometimes seizures. Milder and more severe variants can lead to different ages of onset and different effects on learning and movement.
Treatment
What does that mean for your treatment
No treatment or management approach tied specifically to the GLS gene is currently established for people with pathogenic variants. Separately, the GLS gene is being studied as a drug target in some cancers, where medicines that block glutaminase are under investigation.
Conditions associated with GLS
Gene function
What if the gene works
Your cells constantly turn nutrients into fuel and raw materials. In your body, the GLS gene supports processes that change glutamine into glutamate, a substance cells use every day. Understanding GLS gene function helps explain how cells draw energy from glutamine and keep routine cell activity moving.
The GLS gene helps cells convert glutamine into glutamate. This is a basic step in how your body uses glutamine inside cells.
Glutamate made through the GLS gene can enter the cell’s energy cycle. This helps many cells turn nutrients into usable energy for routine work.
By supplying glutamate, the GLS gene supports the making of other amino acids and glutathione (a protective cell molecule). This helps cells maintain everyday growth, repair, and chemical balance.
What is a variant?
A genetic variant is a small difference in the DNA sequence of a gene. These changes are common and are part of normal human diversity, such as differences in appearance, metabolism, or how the body responds to environmental influences. Many do not have any noticeable effect and simply represent natural genetic variation. In some cases, though, a variant can change the function of a gene more substantially and may contribute to or cause a genetic condition.
Genetic variants
What if the gene does not work
GLS gene variants can change the shape of the protein, make it less stable, or reduce its enzyme activity, which means cells may process glutamine less effectively. In practical terms, how variants influence the GLS gene’s function depends on the change: some missense variants leave partial activity, while more severe splice, nonsense, or frameshift variants can sharply reduce or nearly abolish activity. This spectrum can lead to milder or stronger effects at the cellular level.
How variants are linked to conditions
The clearest link between GLS gene variants and developmental delay is a rare inherited condition often called developmental delay with progressive ataxia and elevated glutamine. People with this diagnosis may have delayed milestones, speech and learning difficulties, and trouble with balance and coordination. High glutamine levels on testing are also part of the condition. Because this is an established monogenic condition, finding pathogenic variants in both copies of the GLS gene can confirm the diagnosis.
A variant is not necessarily a diagnosis
Genetic variants are a routine part of human biology and are widely found in the general population. Most do not have a direct effect on health and simply reflect natural human diversity. For many genes, carrying a variant associated with a condition indicates a possible link rather than a confirmed diagnosis, especially when several genes and environmental factors contribute. In some situations, though, a single well-characterized variant in a particular gene is enough to confirm a diagnosis.
Are there things that can increase or change my risk?
There isn't yet broadly confirmed evidence on specific factors that increase or reduce health risk related to the GLS gene. If a GLS change is found on testing, overall risk usually depends on the exact variant and the health condition involved, and a doctor or genetic counselor can help explain what it means for you or your family.
Inheritance of GLS variants
GLS-related conditions are inherited in an autosomal recessive pattern. This means a child usually inherits one GLS gene variant from each parent, and parents who each carry one variant are typically unaffected. When both parents are carriers, each pregnancy has a 25% chance of a child with the condition, a 50% chance of a child who is a carrier, and a 25% chance of a child with no familial GLS variant. For families learning how GLS gene variants are inherited, sons and daughters are affected equally because the GLS gene is on chromosome 2.
What does my GLS result mean for my family?
For GLS, the best-known inherited condition is passed down in a recessive way, which usually means parents are healthy carriers. For family members, this mainly matters for brothers and sisters, who may also be affected or be carriers, and for other relatives who may want to learn whether they carry the same change. Children of someone with a GLS-related condition will usually be carriers unless the other parent also carries a GLS change.
Genetic information
Genetic testing
How you find out about variants
To look for changes in the GLS gene, a lab uses genetic testing for GLS variants on a blood sample, saliva sample, or cheek swab. The test reads the gene's DNA code and compares it with the usual sequence to identify variants. Results may show a benign variant, a disease linked variant, or a variant of uncertain significance.
When should I consider getting a genetic test?
Genetic testing for the GLS gene may be considered when a child has unexplained developmental delay, movement or balance problems, seizures, or cataracts, especially if blood tests suggest a problem handling glutamine. It can also be helpful when similar features run in the family or parents are related by blood.
A genetic result is only one part of your health story
A genetic result can provide helpful insight, but how much it shows depends on the condition and the specific type of variant involved. Many factors, including lifestyle, environment, age, and medical history, affect how the body functions over time. For some conditions, especially those influenced by many genes, genetic information provides context rather than certainty and is most useful when considered with other parts of care. In other situations, a genetic result can offer a clear answer. In areas like medication response, genetic results can also help put individual experiences into context.
Pharmacogenetics
How variants shape your response to medicine
Genetic variation can affect how people respond to medicines. Small differences in genes can change how the body breaks down a drug, moves it through the bloodstream, or responds to it at its target. This is common and can help explain why the same treatment works well for one person, works less well for another, or causes more side effects in some people.
What is Pharmacogenetics?
Pharmacogenetics examines how genetic differences can shape a person’s response to medications. By looking at the relationship between genes and drugs, it helps explain why the same treatment may work differently from one person to another. For many medicines, genes can affect how strongly a drug works or how the body processes it. This information can support treatment decisions that are more informed and more individualized. More on this topic is available in the LearnHub.
Drugs influenced by the GLS gene
When should I seek medical advice?
There is not yet a broadly confirmed role for this gene in guiding medication response, so questions about medicines, side effects, or changes in how you feel are best discussed with your doctor. They can review your symptoms, other health conditions, and current medicines to decide what matters most for your care.