The YARS2 gene helps mitochondria, the parts of cells that make energy, build certain proteins. The protein made by this gene helps your cells keep muscles, blood cells, and other tissues supplied with energy. If both copies of the YARS2 gene do not work properly because of pathogenic variants, a person can develop a rare inherited condition that often causes muscle weakness, poor exercise tolerance, a buildup of lactic acid in the body, and a form of anemia.
What is a gene?
Genes are stretches of DNA that give cells instructions for making molecules or managing activities in the body. Some carry the code for proteins, which are the parts of cells that do the work. Others are used mostly to regulate when certain processes happen, where they happen, and how active they are. Taken together, genes affect how your body grows and works, and they can also influence how you react to food, stress, or medicines. For a deeper look at this subject, you can find more in the LearnHub.
Overview
YARS2Gene function
What if the gene works
The YARS2 gene helps mitochondria, the parts of cells that make energy, build certain proteins. This supports normal energy production, especially in tissues with high energy needs such as muscles and blood cells.
Risk
What if the gene does not work
Variants in the YARS2 gene can cause a mitochondrial condition with muscle weakness, sideroblastic anemia, and high lactic acid levels. Effects can range from milder to more severe, with symptoms appearing from childhood to adulthood.
Treatment
What does that mean for your treatment
At present, no treatment or drug choice is guided specifically by a pathogenic variant in the YARS2 gene. Care is supportive and based on a person’s symptoms, such as managing anemia, muscle symptoms, or heart involvement, rather than on a YARS2 targeted medicine.
Conditions associated with YARS2
Gene function
What if the gene works
Your cells rely on the YARS2 gene to support the energy work done inside mitochondria, the parts of cells that make most of the body’s usable energy. It helps prepare one amino acid, tyrosine, so mitochondria can build a small but essential set of proteins. Understanding what the YARS2 gene does in mitochondria helps explain how cells keep everyday energy flow steady.
The YARS2 gene makes a protein that attaches tyrosine to its matching transfer RNA inside mitochondria. This loading step gives mitochondria a ready to use amino acid carrier for protein building.
Inside mitochondria, this prepared transfer RNA helps place tyrosine into new proteins at the right time. That allows mitochondria to make several of the proteins they need for normal daily work.
By supporting mitochondrial protein production, the YARS2 gene helps cells make ATP, the main form of usable energy. This keeps routine cell activity running in a steady, coordinated way.
What is a variant?
A genetic variant is a minor change in the DNA sequence within a gene. These changes are common and are part of normal human diversity, including differences in appearance, metabolism, or the way 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 more substantially change how a gene works and may contribute to or cause a genetic condition.
Genetic variants
What if the gene does not work
Variants in the YARS2 gene can weaken or disrupt the YARS2 protein, making it harder for mitochondria, the cell’s energy centers, to build key proteins. Many YARS2 gene variants reduce protein stability or activity, while more severe variants may sharply limit this process and lower cellular energy production. Milder variants may leave some function, while more disruptive changes are often linked to earlier or more pronounced features of mitochondrial myopathy, lactic acidosis, and sideroblastic anemia.
How variants are linked to conditions
Pathogenic variants in the YARS2 gene cause myopathy, lactic acidosis, and sideroblastic anemia 2, often called MLASA2. This YARS2 gene condition is linked to muscle weakness, trouble with exercise, anemia caused by the bone marrow making red blood cells poorly, and high lactate levels on testing. Some people also have heart involvement, including cardiomyopathy (a condition that affects how well the heart pumps).
A variant is not necessarily a diagnosis
Variants in genes are a usual feature of human biology and are widely found in the general population. Most do not directly affect health and instead reflect normal human diversity. For many genes, having a variant associated with a condition suggests a possible link rather than a definite diagnosis, especially when several genes and environmental factors also play a role. 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 YARS2-related illness, risk is mostly set by the gene change itself, usually when both copies of the YARS2 gene are affected. There is not enough evidence to say that lifestyle changes lower the chance of developing it. For people living with the condition, infections and other physical stress can make symptoms worse.
Inheritance of YARS2 variants
YARS2-related conditions follow an autosomal recessive inheritance pattern. This means a person usually inherits one YARS2 variant from each parent, and parents who each carry one variant are typically unaffected themselves. With each pregnancy, two carrier parents have a 25% chance of having a child with the condition, a 50% chance of having a child who is a carrier, and a 25% chance of having a child with no familial variant. In plain terms, the YARS2 inheritance pattern usually appears only when both copies of the gene carry a disease-causing variant.
What does my YARS2 result mean for my family?
For families with a YARS2-related condition, close relatives may also carry the gene change, even if they feel completely well. Brothers and sisters can sometimes be affected or 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 YARS2 gene, doctors use genetic testing for YARS2 variants on a blood or saliva sample. The lab reads the DNA code of the YARS2 gene and may also check for missing or extra pieces. Results can show whether a variant helps explain symptoms or carrier status.
When should I consider getting a genetic test?
If you or your child has unexplained anemia, muscle weakness, easy tiring, or heart problems, especially with a family history of similar problems, genetic testing for the YARS2 gene may help confirm the cause. It can also help clarify an inherited mitochondrial condition, a problem that affects how cells make energy.
A genetic result is only one part of your health story
A genetic finding can provide useful insight, but how much it can tell you varies with the condition and the kind of variant present. The way the body functions over time is also shaped by many factors, including lifestyle, environment, age, and medical history. In some conditions, particularly those affected by many genes, genetic information offers context rather than certainty and makes the most sense when considered with other parts of care. In other situations, a genetic result may give a clear answer. In areas like medication response, genetic results can help put personal experiences in perspective.
Pharmacogenetics
How variants shape your response to medicine
Genetic variation can affect how people respond to medicines. Small differences in genes can change how the body breaks down a drug, moves it into tissues, or responds to it at its target. This helps explain why the same treatment works well for one person, works less well for another, or causes more side effects in some people.
What is Pharmacogenetics?
Pharmacogenetics examines how genetic variation can affect a person’s response to medicines. By looking at the relationship between genes and drugs, it helps explain why the same treatment may work differently from one person to another. For many medications, genes influence either how strongly a drug works or how the body handles it. This information can support treatment decisions that are more informed and more individualized. More detail on this topic is available in the LearnHub.
Drugs influenced by the YARS2 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 medicine, or how treatment fits with your overall health, talk with your doctor or pharmacist.
History
In 2007, researchers identified variants in the YARS2 gene as the cause of a rare inherited condition marked by low red blood cell counts, muscle weakness, and high lactic acid levels, often called MLASA syndrome. This finding helped connect a distinct pattern seen in affected families to one specific gene. From these first observations, research expanded steadily. Additional reports from different countries showed that YARS2-related disease can look somewhat different from one person to another, even within the same family. Over time, these studies made the YARS2 gene part of the broader story of mitochondrial medicine, where scientists were learning how changes in energy-related genes can lead to recognizable health patterns.