The ALG13 gene helps cells attach small sugar chains to proteins, a basic step many proteins need to fold correctly and do their jobs. If this process does not work well, the brain and other body systems may not develop or function as expected. Certain harmful variants in the ALG13 gene are linked to a genetic condition that often includes early seizures, developmental delay, and intellectual disability. Some people may also have low muscle tone or differences in movement, with symptoms varying from person to person.
What is a gene?
Genes are stretches of DNA that give your cells instructions for making molecules or guiding activities in the body. Some genes hold the code for producing proteins, the working components of cells. Others mainly regulate when certain activities happen, where they take place, and how active they are. Together, genes affect how the body grows and works, and they can influence how you respond to food, stress, and medicines. For a deeper look at this topic, you can find more in the LearnHub.
Overview
ALG13Gene function
What if the gene works
The ALG13 gene helps cells add specific sugar pieces to newly made proteins. This supports normal protein folding and cell communication.
Risk
What if the gene does not work
Variants in the ALG13 gene can cause a developmental condition with early seizures, delayed development, and intellectual disability. Effects range from milder to more severe, which can influence when symptoms begin and how strongly speech or learning are affected.
Treatment
What does that mean for your treatment
No ALG13-specific treatment or management approach is currently established for pathogenic variants in the ALG13 gene. Treatment choices usually follow the person’s symptoms, such as seizure type and day-to-day support needs, rather than a gene-directed drug plan.
Conditions associated with ALG13
Gene function
What if the gene works
Many proteins need small sugar chains before they can fold, travel, and do their jobs. The ALG13 gene helps build those sugar chains early in the cell's protein-processing pathway. Understanding what the ALG13 gene does in the body helps explain how cells keep everyday functions running smoothly.
The ALG13 gene helps build an early sugar chain in the cell's protein-processing pathway. This contributes to glycosylation (the process of adding sugar chains to proteins).
These sugar chains help many proteins fold into the right shape and stay stable. They also help guide proteins to the right place inside the cell or onto the cell surface.
Because this sugar-tagging process is used in many tissues, the ALG13 gene supports steady cell function throughout the body. It helps cells manage routine tasks that depend on well-prepared proteins.
What is a variant?
A genetic variant is a minor difference in the DNA sequence within 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 do not have any noticeable effect and are simply part of natural genetic variation. In some cases, though, a variant changes how a gene works more substantially and can contribute to or cause a genetic condition.
Genetic variants
What if the gene does not work
Many disease-associated variants in the ALG13 gene change one protein building block or shorten the protein, which can lower its activity or weaken its link with partner proteins involved in protein glycosylation, the process of attaching sugars to proteins. This is how variants in the ALG13 gene affect protein glycosylation inside cells. Milder variants may leave some function, while more disruptive variants can cause a larger loss and may shape how early developmental and seizure-related features appear.
How variants are linked to conditions
Among the conditions linked to the ALG13 gene, the best established is ALG13-related developmental and epileptic encephalopathy, often called DEE36. Pathogenic variants can cause a genetic condition marked by early onset seizures, developmental delay, and intellectual disability, with features that vary from person to person. Some affected people are also described as having ALG13-congenital disorder of glycosylation.
A variant is not necessarily a diagnosis
Genetic variants are common across the general population and are a normal feature of human biology. Most do not directly affect health and instead reflect natural human diversity. For many genes, a variant associated with a condition points to a possible link rather than a certain diagnosis, particularly when several genes and environmental influences are involved. In some situations, though, one well-characterized variant in a particular gene is enough to confirm a diagnosis.
Are there things that can increase or change my risk?
For ALG13, risk is mainly linked to having a disease-causing change in the gene, and these changes often happen new in the child rather than being passed down. There is not yet broadly confirmed evidence that diet, exercise, or other everyday factors increase or reduce ALG13-related risk.
Inheritance of ALG13 variants
In discussions of how ALG13 gene variants are inherited, the best-established pattern is X linked. Most reported disease-causing changes in the ALG13 gene arise as a new variant in the child rather than being inherited from either parent. If a mother carries an ALG13 variant on one of her X chromosomes, each pregnancy has a 50% chance of passing that variant on. Because ALG13 is on the X chromosome, inheritance can differ between daughters and sons.
What does my ALG13 result mean for my family?
ALG13-related conditions are usually passed on in an X-linked way, so family implications often matter most for the mother and relatives on her side of the family. In some families, female relatives may also carry the variant and may or may not have symptoms, while male relatives can be more seriously affected. Many ALG13 changes happen for the first time in the child, so a parent is not always the source.
Genetic information
Genetic testing
How you find out about variants
ALG13 genetic testing usually analyzes DNA from a blood or saliva sample to look for variants in the ALG13 gene. Labs most often use gene panels, exome sequencing, or genome sequencing and compare your DNA with a reference sequence. A pathogenic variant can help confirm the genetic cause of symptoms.
When should I consider getting a genetic test?
Consider ALG13 genetic testing if a baby or child has unexplained seizures starting early in life, especially along with developmental delays or learning problems. Testing may also make sense when there is a known ALG13 variant in the family or a close relative with a similar pattern of seizures and developmental challenges.
A genetic result is only one part of your health story
Genetic findings can be informative, yet the amount they reveal varies with the condition and the specific type of variant. Over time, the way the body functions is also shaped by factors such as age, environment, lifestyle, and medical history. For some conditions, particularly those affected by many genes, genetic information provides context rather than certainty and makes the most sense when considered with the rest of a person’s care. In other situations, a genetic result can give a clear answer. For medication response, it can also help put personal experiences in context.
Pharmacogenetics
How variants shape your response to medicine
Genetic variation can affect how people respond to medicines. Two people can take the same treatment and have different results because their bodies may break down, transport, or respond to a drug in different ways. These inherited differences are common and can influence how well a medicine works or how likely someone is to notice side effects. Medication response is also shaped by age, liver and kidney function, other health conditions, and other medicines.
What is Pharmacogenetics?
Pharmacogenetics examines how genetic differences affect the way people respond to medications. It studies gene-drug patterns to help explain why the same treatment may work differently from one person to another. For many medicines, genes influence how strongly a drug works or how the body handles it. This information can support more informed, individualized treatment decisions. More information on this topic is available in the LearnHub.
Drugs influenced by the ALG13 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. Talk with your doctor if treatment is not working as expected, side effects are troubling, or symptoms such as seizures or developmental concerns are changing.