The MRPL44 gene helps mitochondria, the parts of your cells that make energy, build the proteins they need to work well. When this gene is not working properly, cells may struggle to make enough energy, especially in tissues with high energy needs such as the brain, muscles, and heart. The protein made by this gene helps your cells keep energy production steady. Pathogenic variants in the MRPL44 gene can cause a rare inherited mitochondrial condition that may lead to low muscle tone, developmental delay, feeding problems, seizures, or heart involvement.
What is a gene?
Genes are stretches of DNA that give your cells instructions to make molecules or regulate processes in the body. Some genes carry the directions for producing proteins, the parts of cells that do much of the work. Other genes mainly control 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 medications. To explore this subject in more detail, you can learn more in the LearnHub.
Overview
MRPL44Gene function
What if the gene works
The MRPL44 gene helps mitochondria, the cell’s energy centers, make proteins. 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
When the MRPL44 gene does not work properly, cells struggle to make energy, which can cause an inherited mitochondrial condition with developmental delay, poor growth, and heart or liver problems. Milder or more severe variants can change onset and severity.
Treatment
What does that mean for your treatment
For people with a pathogenic or loss-of-function variant in the MRPL44 gene, no MRPL44-specific treatment or drug-choice approach is currently established.
Conditions associated with MRPL44
Gene function
What if the gene works
Your cells rely on the MRPL44 gene to support energy production inside mitochondria, the parts of cells that help make usable energy. It helps the mitochondrial protein making machinery build a small set of proteins needed for everyday cell work. Understanding what the MRPL44 gene does in the body helps explain how cells keep energy flowing.
Inside mitochondria, the MRPL44 gene helps form the large part of the mitochondrial ribosome, a cell structure that makes proteins. This allows cells to build a small set of proteins directly from mitochondrial DNA.
The proteins made with help from the MRPL44 gene are used in the system that turns food and oxygen into usable energy. By supporting this step, the gene helps many cells meet their routine energy needs.
The MRPL44 protein works with ribosomal RNA (the RNA framework of the ribosome) and other proteins to keep mitochondrial protein making organized. This steady teamwork helps mitochondria run smoothly during everyday cell activity.
What is a variant?
Genetic variants are small differences in the DNA sequence of a gene. These differences are common and help shape normal human diversity, including variation in appearance, metabolism, and the way the body responds to environmental influences. Many have no noticeable effect and are simply part of natural genetic variation. In some cases, though, a variant can change how a gene functions more significantly and may contribute to or cause a genetic condition.
Genetic variants
What if the gene does not work
Variants in the MRPL44 gene can make the protein unstable, shorten it, or disrupt how it fits into the cell's protein-making machinery inside mitochondria, so cells make fewer energy-related proteins. The way MRPL44 gene variants affect mitochondrial protein production depends on the change: some leave partial activity, while more severe variants can cause a near-complete loss. That difference often shapes how much cellular energy falls and, in affected people, may influence how early and how strongly symptoms appear.
How variants are linked to conditions
Pathogenic variants in the MRPL44 gene cause combined oxidative phosphorylation deficiency 16, a rare inherited mitochondrial condition. The health conditions linked to variants in the MRPL44 gene can include developmental delay, low muscle tone, feeding problems, hearing loss, seizures, poor growth, and sometimes heart involvement or lactic acidosis. Severity varies widely, with some children becoming ill in infancy while others have a milder course.
A variant is not necessarily a diagnosis
Gene variants are a normal feature of human biology and are widely seen in the general population. Most have no direct impact on health and simply represent 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 contribute. In some situations, though, a single well characterized variant in a particular 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 health risk related to the MRPL44 gene. For families with a known MRPL44-related condition, risk is mostly linked to the gene changes inherited at birth, and a doctor or genetic counselor can explain what that means for relatives.
Inheritance of MRPL44 variants
MRPL44-related conditions are inherited in an autosomal recessive pattern. In practical terms, how variants of the MRPL44 gene are inherited usually means a child receives one nonworking copy from each parent, while parents with one changed copy are typically carriers. When both parents carry an MRPL44 variant, each pregnancy has a 25% chance of being affected, a 50% chance of resulting in a carrier child, and a 25% chance of resulting in a child without the familial variants.
What does my MRPL44 result mean for my family?
For families with a disease-causing MRPL44 result, the pattern is usually recessive, which means parents are often healthy carriers and brothers or sisters could also be carriers or, in some families, also be affected. Close relatives may also carry the same change, so the result can matter for family planning and for understanding similar health problems in the family.
Genetic information
Genetic testing
How you find out about variants
To look for changes in the MRPL44 gene, genetic testing for MRPL44 variants usually reads DNA from a blood or saliva sample. Labs may use single gene sequencing or a broader panel, depending on the clinical picture. Results can identify a relevant variant, show no clearly meaningful change, or find a variant whose significance is still being clarified.
When should I consider getting a genetic test?
Genetic testing for the MRPL44 gene may be considered if a baby or child has signs of a rare inherited condition that affects how cells make energy, often with heart problems, slow development, or high lactic acid levels. It can also help when there is a family history of a similar condition.
A genetic result is only one part of your health story
Genetic test results can provide useful insight, but how much they explain depends on the condition and the kind of variant involved. Over time, the way your body functions is shaped by many factors, including lifestyle, environment, age, and medical history. For some conditions, especially those influenced by many genes, genetic information offers context rather than certainty and is best understood alongside other parts of care. In other situations, a genetic result may give a clear answer. In areas such as medication response, genetic results can also help put individual experiences into perspective.
Pharmacogenetics
How variants shape your response to medicine
Genetic variation can affect how people respond to medicines. Some people break down a medication faster or slower than others, so the same treatment may work differently from one person to the next. These inherited differences are common and can influence how much benefit a person gets or how sensitive they are to side effects. Medication response also depends on other factors, including age, kidney and liver function, and other medicines being taken.
What is Pharmacogenetics?
Pharmacogenetics examines how genetic differences shape the way people respond to medications. It focuses on links between genes and drugs to help explain why the same treatment can work differently from one person to another. For many medicines, genes influence both how strongly a drug works and how the body processes it. This information can support more informed and more individualized treatment choices. To explore this topic in greater detail, you can learn more in the LearnHub.
Drugs influenced by the MRPL44 gene
When should I seek medical advice?
There is not yet a broadly confirmed role for this gene in guiding medication choices, so any concerns about medicines, side effects, or your overall health are best discussed with your doctor.
History
MRPL44 entered the medical literature during the period when researchers were cataloging the many genes involved in mitochondrial biology. In recent decades, knowledge has built on a long tradition of observing inherited traits. As genome mapping improved in the late 20th and early 21st centuries, scientists identified the MRPL44 gene as part of the group of genes linked to the mitochondrial ribosome. Building on this early work, scientists uncovered more about the gene when rare inherited variants were connected with mitochondrial disease in affected families. That shift moved MRPL44 from a largely research focused gene into a clearer clinical setting. Today, its history is mainly tied to advances in mitochondrial genetics rather than to a single famous public story.