The NHLRC1 gene makes a protein called malin, which helps cells control glycogen, the stored form of sugar, and clear unneeded proteins. When this gene does not work properly, clumps of abnormal glycogen can build up, especially in brain cells. This gene plays an important role in keeping nerve cells stable, so pathogenic variants can cause Lafora disease, a rare inherited epilepsy. People with this condition may develop seizures, jerking movements, and problems with thinking over time.
What is a gene?
A gene is a stretch of DNA that carries instructions cells can use to make molecules or regulate processes in the body. Some genes provide the information needed to make proteins, which are the working parts of cells. Other genes mainly control when certain processes happen, where they take place, and how strongly they occur. Together, genes influence how the body develops and works, and they can shape how you respond to food, stress, or medications. To look more closely at this topic, you can learn more in LearnHub.
Overview
NHLRC1Gene function
What if the gene works
The NHLRC1 gene helps cells control how glycogen, the stored form of sugar, is made and cleared. Its protein works with partner proteins to reduce buildup of poorly formed glycogen, especially in the brain.
Risk
What if the gene does not work
Variants in the NHLRC1 gene can cause Lafora disease, a progressive epilepsy with seizures, jerking movements, and worsening thinking and daily function. Milder and more severe variants can affect when symptoms begin and how strongly the condition affects daily life.
Treatment
What does that mean for your treatment
No treatment or drug selection approach specific to pathogenic variants in the NHLRC1 gene is currently established, so care remains symptom based rather than guided by the variant itself. In Lafora disease, research is exploring treatments that reduce abnormal glycogen buildup, along with early gene based approaches, but these are not standard care.
Conditions associated with NHLRC1
Gene function
What if the gene works
Your cells use the NHLRC1 gene to help manage glycogen, the stored form of sugar. It works closely with laforin, a partner protein made from the EPM2A gene, to keep this stored fuel organized. Understanding how the NHLRC1 gene helps control glycogen makes its role in everyday cell energy handling easier to picture.
The NHLRC1 gene helps cells regulate glycogen, the way your body stores extra sugar for later use. It supports glycogen quality control so this stored fuel stays in a form cells can handle smoothly.
Its protein adds small tags to selected proteins so cells can adjust, move, or recycle them at the right time. This helps keep glycogen handling and other routine cell tasks coordinated.
The NHLRC1 gene works closely with laforin, a partner protein made from the EPM2A gene. Together they guide how cells monitor stored sugar and keep energy storage well organized.
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, including differences in appearance, metabolism, or how the body responds to environmental influences. Many variants do not have any noticeable effect and are simply part of natural 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 NHLRC1 gene can change how NHLRC1 variants affect protein function by making the protein unstable, unusually short, or less able to work with partner proteins that control glycogen handling in cells. This can allow abnormal glycogen clumps, called Lafora bodies, to build up. Some variants leave partial activity, while more severe variants greatly reduce or eliminate it, which can influence how early Lafora disease appears and how strongly it affects a person.
How variants are linked to conditions
Pathogenic variants in both copies of the NHLRC1 gene cause Lafora disease, also called progressive myoclonus epilepsy type 2B. The link between the NHLRC1 gene and Lafora disease is well established. Symptoms often begin in the teen years with seizures and sudden muscle jerks, and many people later develop problems with balance, speech, memory, or thinking.
A variant is not necessarily a diagnosis
Variants in genes are a routine part of human biology and are widespread in the general population. 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 indicates a possible link rather than a definite diagnosis, especially when several genes and environmental factors play a role. In some situations, though, a single well-characterized variant in a particular gene is enough to confirm a diagnosis.
Are there things that can increase or change my risk?
For NHLRC1, risk is mainly shaped by inheritance: Lafora disease usually happens only when a child inherits harmful NHLRC1 changes from both parents. A family history of the condition, or parents who are related by blood, can raise the chance of this happening. Once those gene changes are present, lifestyle changes are not known to prevent the condition.
Inheritance of NHLRC1 variants
Variants in the NHLRC1 gene are inherited in an autosomal recessive pattern, which is the key point in understanding the inheritance of NHLRC1 gene variants. This means a person usually develops NHLRC1-related Lafora disease only when they inherit two disease-causing variants, one from each parent. Parents who each carry one variant typically do not have the condition themselves, but with each pregnancy they have a 25% chance of having an affected child, a 50% chance of having a child who is a carrier, and a 25% chance of having a child with neither variant.
What does my NHLRC1 result mean for my family?
For families affected by changes in the NHLRC1 gene, close relatives may also carry the same gene change, even if they do not have symptoms. Brothers and sisters can sometimes be affected too, while parents are often healthy carriers. Other relatives may want to learn whether they are carriers, especially if they are planning children.
Genetic information
Genetic testing
How you find out about variants
NHLRC1 genetic testing for Lafora disease usually uses a blood or saliva sample. A lab reads the NHLRC1 gene and checks for variants, often as part of an epilepsy gene panel or a broader sequencing test. Finding two pathogenic variants, one from each parent, can confirm NHLRC1-related Lafora disease.
When should I consider getting a genetic test?
Consider testing for changes in the NHLRC1 gene if someone has unexplained seizures and sudden muscle jerks that began in the teen years, especially if symptoms are getting worse over time. It can also be helpful when Lafora disease runs in the family or when a brother or sister has already been diagnosed.
A genetic result is only one part of your health story
Genetic results can be informative, but how much they reveal varies based on the condition and the type of variant involved. Many factors also shape how the body works over time, 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 most useful when considered 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 context.
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 through the body, or responds to its effects. This helps explain why the same treatment may work well for one person, seem less effective for another, or cause more side effects in someone else.
What is Pharmacogenetics?
Pharmacogenetics examines how genetic differences affect the way people respond to medications. It studies the relationship between genes and drugs 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 processes it. This information can support more informed, more individualized treatment decisions. To learn more about this topic, you can explore the LearnHub.
Drugs influenced by the NHLRC1 gene
When should I seek medical advice?
There is not yet a broadly confirmed role for this gene in guiding medication choices, so general questions about symptoms, treatment, side effects, or how medicines may affect you are best discussed with your doctor.
History
Throughout history, people have described features that hinted at this gene. NHLRC1 became linked to a long-recognized inherited epilepsy condition after early 20th century reports of Lafora disease, named for neurologist Gonzalo Rodríguez Lafora, who described the characteristic cell deposits seen in affected tissue. For many years, the condition was identified by these tissue findings and by its pattern in families. From these first observations, research expanded steadily. In the early 2000s, researchers identified the NHLRC1 gene as one of the key genes involved, alongside EPM2A, which helped clarify why some families with the same condition had different genetic causes. This discovery made diagnosis more precise and deepened understanding of this rare inherited condition.