Your cells depend on the SUCLA2 gene when they need to make energy inside mitochondria, the parts of cells that act like power centers. If the gene does not work properly, the body may struggle to supply enough energy, especially to the brain and muscles. People with harmful variants in the SUCLA2 gene can develop a rare inherited mitochondrial condition with developmental delay, low muscle tone, movement problems, and sometimes hearing loss. Symptoms and severity can vary from person to person.
What is a gene?
A gene is a stretch of DNA that holds instructions your cells use to make molecules or manage processes in the body. Some genes carry the directions for producing proteins, the parts of cells that do the work. Others mainly help regulate when, where, and how strongly certain processes take place. Taken together, genes affect how the body grows and works, and they can influence how you respond to food, stress, or medicines. For a deeper look at this topic, more information is available in LearnHub.
Overview
SUCLA2Gene function
What if the gene works
The SUCLA2 gene helps mitochondria, your cells' energy centers, make usable energy from food. This is especially important in muscles and the brain.
Risk
What if the gene does not work
Variants in the SUCLA2 gene can cause a mitochondrial condition, often starting in infancy or childhood, with low muscle tone, movement problems, developmental delay, hearing loss, and methylmalonic acid buildup. Milder or more severe variants can affect timing and severity.
Treatment
What does that mean for your treatment
No treatment or medication choice is currently guided specifically by a pathogenic variant in the SUCLA2 gene; care remains supportive and based on symptoms.
Conditions associated with SUCLA2
Gene function
What if the gene works
Your cells need a steady way to turn food into usable energy, and the SUCLA2 gene supports one key step in that process. It works inside mitochondria, the parts of cells that make most of their energy. This is part of how the SUCLA2 gene helps make energy in mitochondria during everyday cell activity.
In mitochondria, the SUCLA2 gene helps run the citric acid cycle, a central energy pathway. It supports one of the cycle's middle steps, helping cells draw usable energy from food.
This step helps make ATP, the main energy currency used by your cells. That gives cells a direct, steady source of power for routine activity.
By supporting this pathway, the SUCLA2 gene helps cells use parts of carbohydrates, fats, and proteins for energy. This helps keep everyday cell activity moving in an organized way.
What is a variant?
A genetic variant is a minor difference in the DNA sequence of a gene. These differences are common and help explain normal human diversity, including variation in appearance, metabolism, and the way the body responds to environmental influences. Many do not cause any noticeable effect and are simply part of natural genetic variation. Sometimes, however, a variant changes how a gene functions more substantially and can contribute to or cause a genetic condition.
Genetic variants
What if the gene does not work
Variants in the SUCLA2 gene can make the mitochondrial protein unstable, lower its activity, or stop it from joining its usual protein partner. In practical terms, this is how SUCLA2 gene variants affect the protein and reduce the cell's ability to keep mitochondrial DNA at healthy levels. Some changes partly reduce function, while more disruptive variants can nearly eliminate it, which often lines up with earlier and more marked features of the SUCLA2-related condition.
How variants are linked to conditions
Pathogenic variants in the SUCLA2 gene cause a rare inherited mitochondrial condition called mitochondrial DNA depletion syndrome with encephalomyopathy and methylmalonic aciduria. This SUCLA2 gene condition usually starts in infancy or early childhood and may include low muscle tone, developmental delay, movement problems, hearing loss, and seizures. Some people have a Leigh syndrome spectrum diagnosis, and disease-causing variants in both copies of the SUCLA2 gene can confirm the condition.
A variant is not necessarily a diagnosis
Variants are a routine feature of human biology and are widely found across the general population. Most do not directly affect health and instead reflect normal human diversity. In many genes, having a variant connected with a condition points to a possible link rather than a confirmed diagnosis, particularly when several genes and environmental influences also play a role. Sometimes, though, one well-characterized variant in a particular gene is enough to establish a diagnosis.
Are there things that can increase or change my risk?
For SUCLA2, risk is mainly shaped by inheritance rather than lifestyle or everyday exposures. If both biological parents carry a harmful SUCLA2 change, each pregnancy has a 25% chance of the child having the condition and a 50% chance of the child being a carrier.
Inheritance of SUCLA2 variants
SUCLA2-related conditions are inherited in an autosomal recessive pattern. This means a person usually develops the condition only if they inherit two disease-causing variants in the SUCLA2 gene, one 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 child who is a carrier, and a 25% chance of having a child with neither variant. In practical terms, how SUCLA2 is inherited usually means the condition can appear in brothers or sisters even when the parents have no symptoms.
What does my SUCLA2 result mean for my family?
For families with a disease-causing SUCLA2 result, close relatives may also carry the same gene change, even if they feel well. Brothers and sisters may be affected or may be carriers, and parents are usually carriers. Other relatives, such as aunts, uncles, and cousins, may also carry the change, so the result can matter beyond one person.
Genetic information
Genetic testing
How you find out about variants
To find out whether you carry a variant in the SUCLA2 gene, doctors use genetic testing for SUCLA2 gene variants on a blood sample, saliva sample, or cheek swab. The lab reads the gene’s DNA code and may also check for missing or extra pieces, which can help confirm a diagnosis or show whether someone is a carrier.
When should I consider getting a genetic test?
Genetic testing for the SUCLA2 gene may be considered when a baby or child has signs of a rare inherited energy condition, such as low muscle tone, feeding trouble, developmental delay, hearing loss, or unusual movement problems. It can also be useful when there is a family history of this condition or when both parents are known carriers.
A genetic result is only one part of your health story
A genetic result can provide useful insight, but how much it reveals depends on the condition and the kind of variant involved. Over time, many factors, including lifestyle, environment, age, and medical history, influence how the body works. For some conditions, especially those shaped by many genes, genetic information provides context rather than certainty and is most useful when considered alongside other parts of care. In other situations, a genetic result may 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 your body responds to medicines. Some people break down a drug more slowly or more quickly, while others may be more or less sensitive to its effects. This helps explain why the same treatment can work well for one person but cause fewer benefits or more side effects in another. These differences are common and are one part of the reason medication response can vary from person to person.
What is Pharmacogenetics?
Pharmacogenetics examines how differences in genes affect the way a person responds to medicines. It studies gene and drug patterns to better explain why the same treatment can work differently from one person to another. For many medications, genes influence how strongly a drug works or how the body handles it. This understanding can support treatment decisions that are more informed and more personalized. To explore this topic in greater detail, you can learn more in the LearnHub.
Drugs influenced by the SUCLA2 gene
When should I seek medical advice?
There is not yet a broadly confirmed role for this gene in guiding medication choice or dose. If you have concerns about side effects, a new prescription, or how any medicine may affect your overall health, talk with your doctor or pharmacist.
History
SUCLA2 entered the medical literature through studies of children with an inherited mitochondrial condition marked by low muscle tone, movement problems, and hearing loss. In the early 2000s, researchers linked pathogenic variants in the SUCLA2 gene to mitochondrial DNA depletion syndrome, helping clarify a cause of a condition that had previously been recognized mainly by its clinical features. From these first observations, research expanded steadily. Reports from families in different regions, including the Faroe Islands, helped establish recurring patterns and supported SUCLA2 as a distinct disease gene. As genetic testing improved, the historical picture became clearer, and SUCLA2 was recognized as part of the growing field of mitochondrial medicine.