The NDUFS5 gene helps your cells make energy inside mitochondria, the parts of cells that act like tiny power plants. This gene plays an important role in tissues that need a steady energy supply, especially the brain, muscles, and heart. If it does not work properly, cells may struggle to make enough energy, which can lead to a mitochondrial condition with features such as developmental delay, low muscle tone, weakness, movement problems, seizures, or heart problems.
What is a gene?
A gene is a piece of DNA that holds information cells use to make molecules or to regulate processes in the body. Some genes provide the instructions for producing proteins, which are the working parts of cells. Others mainly help govern when certain processes happen, where they take place, and how strong their activity is. In combination, 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, you can find more in the LearnHub.
Overview
NDUFS5Gene function
What if the gene works
The NDUFS5 gene helps mitochondria, the cell’s energy makers, turn food and oxygen into energy. This supports energy production in tissues with high energy needs, such as the brain, muscles, and heart.
Risk
What if the gene does not work
Biallelic variants in the NDUFS5 gene can cause mitochondrial complex I deficiency, often with onset in infancy, developmental delay, low muscle tone, brain involvement, and lactic acidosis. Milder or more severe variants can alter timing and severity.
Treatment
What does that mean for your treatment
No treatment or medication choice is currently guided specifically by pathogenic or loss-of-function variants in the NDUFS5 gene; care is symptom-based and follows general management for mitochondrial disease rather than a NDUFS5-specific approach.
Gene function
What if the gene works
Your cells need a steady supply of energy to move, grow, and handle routine tasks. The NDUFS5 gene supports this process inside mitochondria, the parts of cells that make most of your usable energy. Understanding what the NDUFS5 gene does in your cells helps show how the body powers everyday functions.
The NDUFS5 gene makes one small part of complex I, the first major step in the mitochondrial energy chain. This helps your cells turn energy from food into ATP, the fuel they use every day.
Inside mitochondria, this protein supports the movement of electrons through complex I. That early step helps create stored energy across the mitochondrial membrane, which is then used to make ATP.
Its protein helps complex I keep the right shape in the mitochondrial membrane. A stable complex lets your cells make energy in a steady, coordinated way.
What is a variant?
A genetic variant is a minor change in the DNA sequence of a gene. These changes are common and are part of normal human diversity, including differences in appearance, metabolism, and how the body responds to environmental influences. Many have no noticeable effect and simply represent natural genetic variation. Sometimes, though, a variant changes how a gene functions more substantially and may contribute to or cause a genetic condition.
Genetic variants
What if the gene does not work
Variants in the NDUFS5 gene can change the shape or stability of a small protein needed to build complex I, part of the cell’s energy system in mitochondria. This shows how NDUFS5 gene variants affect complex I: milder variants may leave some function, while more severe variants can sharply reduce assembly or make the complex unstable. That can lower cellular energy, and in established mitochondrial disease, more disruptive variants often go along with earlier or more marked symptoms.
How variants are linked to conditions
Current evidence does not yet show a broadly confirmed link between NDUFS5 gene variants and a specific health condition, though this may change as research grows. Anyone with a confirmed NDUFS5-related diagnosis should rely on guidance from their doctor or genetic counselor rather than general information.
A variant is not necessarily a diagnosis
Genetic variants are common across the general population and are a usual part of human biology. Most do not directly affect health and instead reflect normal human diversity. For many genes, carrying a variant associated with a condition suggests a possible link rather than a definite diagnosis, especially when several genes and environmental factors also contribute. 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?
For NDUFS5, there is no broadly confirmed evidence that specific lifestyle or environmental factors meaningfully change the chance of developing an NDUFS5-related condition. Risk is mainly tied to whether a child inherits disease-causing changes in both copies of the NDUFS5 gene, so people with concerns about family risk can speak with a doctor or genetic counselor.
Inheritance of NDUFS5 variants
Variants in the NDUFS5 gene are inherited in an autosomal recessive pattern. In practical terms, NDUFS5 gene inheritance usually means a child has to receive one altered copy from each parent to have an NDUFS5-related condition. Parents who each carry one variant are usually unaffected themselves, and with each pregnancy there is a 25% chance the child will inherit both variants, a 50% chance the child will be a carrier, and a 25% chance the child will inherit neither variant. Mothers and fathers can pass these variants on equally.
What does my NDUFS5 result mean for my family?
For NDUFS5, the main family pattern is recessive, which means parents of an affected child are usually healthy carriers. Brothers and sisters may also be affected or may be carriers, and other close relatives could be carriers too. Because of that, family members may want to talk with their care team about whether the result has meaning for them.
Genetic information
Genetic testing
How you find out about variants
NDUFS5 genetic testing uses a blood, saliva, or cheek swab sample to read the DNA in the NDUFS5 gene and look for variants. Results can help confirm a diagnosis in someone with signs of mitochondrial disease or show whether a family variant is present.
When should I consider getting a genetic test?
Testing for the NDUFS5 gene may be worth considering when a baby or child has signs of a mitochondrial condition, such as developmental delay, low muscle tone, seizures, feeding problems, or repeated episodes of high lactic acid in the blood. It can also help when a close family member has a confirmed NDUFS5 change or a similar unexplained condition.
A genetic result is only one part of your health story
A genetic test result can provide useful insight, but how much it explains depends on the condition and the kind of variant involved. Over time, many factors, including lifestyle, environment, age, and medical history, also affect how the body functions. For some conditions, particularly those shaped by many genes, genetic information offers context rather than certainty and is most helpful 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 also help put personal experiences in context.
Pharmacogenetics
How variants shape your response to medicine
Genetic variation can affect how people respond to medicines. This helps explain why the same treatment works well for one person, has less effect in another, or causes more side effects in someone else. Part of the reason is that inherited differences can change how the body breaks down a drug, moves it through the body, or responds to it at its target.
What is Pharmacogenetics?
Pharmacogenetics is the area of medicine that examines how genetic differences shape the way people respond to medications. It studies patterns between genes and drugs to understand more clearly why the same treatment can work differently from one person to another. For many medicines, genes influence either how strongly a drug works or how the body handles it. This understanding can support treatment decisions that are more informed and more individualized. To explore this topic in greater detail, you can learn more in the LearnHub.
Drugs influenced by the NDUFS5 gene
When should I seek medical advice?
There is not yet a broadly confirmed role for this gene in guiding medication choices. Questions about medicines, side effects, or changes in how you feel are best discussed with your doctor or pharmacist, especially before starting a new treatment or if symptoms worsen.