The protein made by the FOXRED1 gene helps your cells assemble complex I, an important part of the mitochondria that turns food into usable energy. If this gene does not work properly, cells may not make enough energy, especially in the brain and muscles. Harmful variants in the FOXRED1 gene can cause a rare mitochondrial condition with developmental delay, low muscle tone, feeding difficulties, seizures, movement problems, or lactic acidosis (too much acid in the blood). Symptoms often begin in infancy or childhood, though severity can vary.
What is a gene?
Genes are stretches of DNA that hold instructions your cells use to make molecules or regulate processes in the body. Some genes carry the directions for producing proteins, which are the active components of cells. Others are used mainly to guide when certain processes happen, where they take place, and how active they are. Taken together, genes affect how the body grows and works, and they may influence how you respond to food, stress, or medicines. For a deeper look at this topic, you can read more in the LearnHub.
Overview
FOXRED1Gene function
What if the gene works
The FOXRED1 gene helps build complex I, a key part of mitochondria, the parts of cells that make energy. This supports normal energy production, especially in the brain, muscles, and other tissues with high energy needs.
Risk
What if the gene does not work
When the FOXRED1 gene does not work properly, it most often causes mitochondrial complex I deficiency, usually affecting the brain with developmental delay, seizures, or lactic acidosis. Milder or more severe variants can change onset, severity, and features.
Treatment
What does that mean for your treatment
For people with a pathogenic or loss-of-function variant in the FOXRED1 gene, no treatment or drug choice plan that is specific to this gene is currently established. Research is exploring broader treatments for mitochondrial disease, but none is a guideline-based therapy aimed specifically at the FOXRED1 gene.
Conditions associated with FOXRED1
Gene function
What if the gene works
Your cells need a steady supply of energy to do everyday work. Inside mitochondria, the FOXRED1 gene helps set up one of the key steps in that process. This is part of how the FOXRED1 gene helps mitochondria make energy for tissues that stay active all day, including the brain and muscles.
The FOXRED1 gene helps your cells build complex I, a major protein group inside mitochondria (the parts of cells that make most energy). This step is important for creating a working energy system.
A well built complex I can pass electrons through the mitochondrial energy chain in a controlled way. This supports oxidative phosphorylation (the main process cells use to make ATP, their usable energy).
By supporting mitochondrial energy making, FOXRED1 helps cells meet everyday demands such as movement, signaling, and growth. This is especially helpful in tissues that need a constant energy supply.
What is a variant?
A genetic variant is a small difference in the DNA sequence within a gene. These differences are common and are part of normal human diversity, including differences in appearance, metabolism, or 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 works more significantly and may contribute to or cause a genetic condition.
Genetic variants
What if the gene does not work
Variants in the FOXRED1 gene can make its protein unstable, poorly folded, or less able to help assemble complex I, a key energy-making part of mitochondria (the cell’s energy-making parts). This helps explain how FOXRED1 gene variants affect mitochondrial function at a cellular level. Milder variants may leave some activity in place, while more severe variants can cause little to none, which may influence how early related mitochondrial disease appears and how marked it is.
How variants are linked to conditions
Pathogenic variants in the FOXRED1 gene are linked to a rare inherited mitochondrial condition called mitochondrial complex I deficiency. In patient-friendly terms, FOXRED1 gene variants linked to conditions most often mean early-onset brain and body energy problems, with developmental delay, low muscle tone, seizures, feeding difficulties, or episodes of lactic acidosis. Some people also have features of Leigh syndrome, a neurological condition seen in some mitochondrial diseases.
A variant is not necessarily a diagnosis
Genetic variants are a routine part of human biology and are widely found across 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 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 FOXRED1, risk is mainly shaped by the genes inherited at birth, especially when a child receives a changed copy from each parent. There is not yet broadly confirmed evidence that diet, exercise, or other everyday factors meaningfully increase or reduce the chance of FOXRED1-related illness.
Inheritance of FOXRED1 variants
FOXRED1-related conditions are inherited in an autosomal recessive pattern. In practical terms, a child usually needs to inherit one changed copy of the FOXRED1 gene from each parent to be affected. Parents who each carry one FOXRED1 variant are typically unaffected carriers, 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. This FOXRED1 inheritance pattern affects sons and daughters equally.
What does my FOXRED1 result mean for my family?
FOXRED1-related conditions are usually passed down in a recessive way, so family members may be healthy carriers without knowing it. Brothers and sisters of someone with a disease-causing FOXRED1 result may also be affected or may be carriers. Parents are usually carriers, and other relatives on both sides of the family may also carry the changed gene.
Genetic information
Genetic testing
How you find out about variants
To find out whether you carry a variant in the FOXRED1 gene, a lab can analyze DNA from a blood sample, saliva sample, or cheek swab. FOXRED1 genetic testing reads the gene’s DNA code and compares it with known variants, with results usually reported as positive, negative, or uncertain.
When should I consider getting a genetic test?
Genetic testing for the FOXRED1 gene may be considered when a baby or child has signs of a rare condition that affects how cells make energy, such as developmental delay, low muscle tone, seizures, feeding problems, or high lactic acid levels. It can also help when similar early childhood illness runs in the family.
A genetic result is only one part of your health story
Genetic results can be informative, but how much they clarify depends on the condition and on the type of variant. 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 offers context rather than certainty and is best considered together with other parts of care. In other situations, a genetic result can give a clear answer. For medication response, genetic results may 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 DNA can change how the body breaks down a drug, moves it through the body, or responds to it at its target. 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. These differences are common and are one part of why medication response can vary from person to person.
What is Pharmacogenetics?
Pharmacogenetics examines how genetic differences can affect the way a person responds to medications. It studies the relationship between genes and drugs to better understand why the same treatment may work differently from one person to another. For many medicines, genes help influence how strongly a drug works or how the body handles it. This information can support more informed and individualized treatment decisions. You can learn more about this topic in the LearnHub.
Drugs influenced by the FOXRED1 gene
When should I seek medical advice?
There is not yet a broadly confirmed role for this gene in guiding how medicines are chosen or used, so questions about symptoms, side effects, or medication changes are best discussed with your doctor.
History
FOXRED1 entered the medical literature through studies of children and adults with an inherited mitochondrial condition, with reports emerging in the early 2010s as genetic sequencing became more widely used. Initially understood only through visible traits, later recognized as tied to a specific gene, FOXRED1 became part of the growing effort to explain rare causes of complex I deficiency. From these first observations, research expanded steadily. Additional families from different countries helped confirm that harmful variants in the FOXRED1 gene could underlie a similar pattern of illness, while also showing that features can vary from person to person. This work placed FOXRED1 within the broader history of solving rare metabolic conditions through modern DNA testing.