The UQCRB gene helps make energy inside mitochondria, the parts of cells that act as tiny power stations. The protein made by this gene helps your cells carry out a key step in energy production, especially in organs with high energy needs such as the brain and muscles. If the UQCRB gene does not work properly, cells may produce less energy, which can lead to a mitochondrial condition with features such as developmental delay, muscle weakness, poor growth, or high lactic acid levels in the blood. UQCRB is mainly known in medical genetics rather than in popular culture.
What is a gene?
Genes are stretches of DNA that give your cells instructions they can use to make molecules or regulate processes in the body. Some genes carry the information needed to produce proteins, the parts of cells that do much of the work. Other genes mostly control when certain processes happen, where they take place, and how strongly they operate. Together, genes affect how the body develops and functions, and they can influence how you respond to food, stress, or medications. For a more detailed look at this topic, you can learn more in the LearnHub.
Overview
UQCRBGene function
What if the gene works
The UQCRB gene helps form part of a protein complex in mitochondria, the parts of cells that make energy. This supports a key step in energy production used by nearly all tissues.
Risk
What if the gene does not work
Variants in the UQCRB gene can reduce the cell's ability to make energy, causing a rare mitochondrial condition. People may develop low blood sugar, excess lactic acid, and liver or brain problems, with severity ranging from milder to more severe.
Treatment
What does that mean for your treatment
No UQCRB-specific treatment or management approach is currently established. Care is usually based on a person’s symptoms rather than a drug choice linked to the UQCRB gene. In research, the UQCRB gene is being studied as a possible drug target in some cancers and in pathways that drive new blood vessel growth.
Conditions associated with UQCRB
Gene function
What if the gene works
Inside mitochondria, your cells use the UQCRB gene to keep energy production moving. It supports one of the middle steps in the chain that turns fuel from food into ATP, the main form of usable cellular energy. This helps tissues with ongoing energy needs keep working smoothly.
The UQCRB gene helps one mitochondrial protein group pass tiny electrical charges along the cell's energy pathway. This is a key step in turning fuel from food and oxygen into usable energy.
During this step, mitochondria move protons (tiny charged particles) across their inner membrane. This creates a stored charge, like a small battery, that helps cells make ATP, their main energy molecule.
Its protein is part of complex III, one of the linked protein groups that power mitochondrial energy production. By helping this group stay properly organized, the UQCRB gene supports steady energy supply in tissues that need constant power.
What is a variant?
A genetic variant is a slight change in the DNA sequence within a gene. These changes are common and help shape normal human diversity, such as differences in appearance, metabolism, or how the body responds to environmental influences. Many variants have no noticeable effect and simply reflect the natural range of 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
Variants in the UQCRB gene can alter the protein's shape or stability, so a key mitochondrial energy complex may not assemble properly or move electrons efficiently. This is how UQCRB gene variants affect protein function in mitochondria, leading to lower energy output and more oxidative stress (cell damage from unstable oxygen molecules). Milder variants may leave some activity, while more severe variants can cause a larger loss of function and are more often linked to earlier, broader mitochondrial disease features.
How variants are linked to conditions
Pathogenic variants in the UQCRB gene cause mitochondrial complex III deficiency, a very rare inherited condition. People with this diagnosis may have low muscle tone, feeding problems, developmental delay, episodes of high lactic acid, or liver involvement, although features can vary. Some may also have short stature or exercise intolerance.
A variant is not necessarily a diagnosis
In the general population, genetic variants are common and are a normal part of human biology. Most do not have a direct effect on health and instead reflect natural human diversity. For many genes, carrying a variant associated with a condition suggests a possible link rather than a definite diagnosis, especially when multiple genes and environmental factors are involved. In some cases, though, a single well-characterized variant in a specific gene can be 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 risk related to the UQCRB gene. People with concerns about their personal or family risk can talk with a doctor or genetic counselor about what this result may mean for them.
Inheritance of UQCRB variants
UQCRB-related conditions are inherited in an autosomal recessive pattern. This means a child usually inherits one UQCRB gene variant from each parent, and parents who carry one variant are typically unaffected carriers. When both parents are carriers, each pregnancy has a 25% chance of the child inheriting both variants, a 50% chance of being a carrier, and a 25% chance of inheriting neither variant. In practical terms, UQCRB inheritance usually follows the same pattern for sons and daughters because this gene is on chromosome 8.
What does my UQCRB result mean for my family?
Changes in the UQCRB gene linked to illness are usually passed down in a recessive pattern, so close relatives may be carriers even if they feel well. Brothers and sisters could also have the same condition or be carriers, and future children in the family may be affected if both parents carry a changed copy. This kind of result can matter for family planning and for relatives who want to understand their own chances of carrying the same gene change.
Genetic information
Genetic testing
How you find out about variants
UQCRB genetic testing usually uses a blood or saliva sample. A lab reads the DNA in the UQCRB gene, often as part of a multigene panel, whole exome sequencing, or whole genome sequencing, and compares it with the usual sequence to look for variants that may help explain a person’s symptoms.
When should I consider getting a genetic test?
Genetic testing may be worth considering if a child or family member has signs of a rare energy-production condition, such as severe low muscle tone, feeding problems, developmental delays, or repeated low blood sugar, especially when similar problems run in the family. UQCRB is usually checked as part of a broader mitochondrial gene panel.
A genetic result is only one part of your health story
Genetic results can provide useful insight, but how much they explain varies by the condition and the type of variant involved. Many factors, including lifestyle, environment, age, and medical history, also influence how the body works over time. In some conditions, especially those shaped by many genes, genetic information provides context rather than certainty and is most useful when viewed alongside other parts of care. In other situations, a genetic result can offer a clear answer. In areas such as medication response, genetic results can help put individual experiences into context.
Pharmacogenetics
How variants shape your response to medicine
Genetic variation can affect how people respond to medicines. This helps explain why the same medication may work well for one person, do less for another, or cause more side effects in someone else. Small differences in how the body breaks down, moves, or responds to a drug are common, and they can influence both treatment benefit and medication sensitivity.
What is Pharmacogenetics?
Pharmacogenetics examines how genetic differences can affect a person’s response to medicines. By studying the links between genes and drugs, it helps explain why the same treatment may work differently from one person to another. For many medicines, genes can influence how the body processes a drug or how strong its effects are. This information can support more informed and more personalized treatment decisions. More detail on this topic is available in the LearnHub.
Drugs influenced by the UQCRB gene
When should I seek medical advice?
There is not yet a broadly confirmed role for this gene in guiding medication choice or dose, so questions about symptoms, side effects, or how your medicines may affect you are best discussed with your doctor.