The SLC37A4 gene helps move a sugar phosphate inside cells so the liver, kidneys, and white blood cells can manage stored energy and support normal immunity. If it does not work properly, the body may struggle to keep blood sugar steady between meals and some immune cells may not work well. Pathogenic variants in the SLC37A4 gene cause glycogen storage disease type Ib, which can lead to low blood sugar, an enlarged liver, slow growth, and repeated infections. This gene is mainly known in medical genetics rather than popular culture.
What is a gene?
A gene is a stretch of DNA that gives your cells information they can use to make molecules or regulate processes in the body. Some genes provide the instructions for making proteins, the parts of cells that do much of the work. Other genes mostly help determine when certain processes happen, where they take place, and how strongly they run. Taken together, genes influence how the body develops and functions, and they can affect how you respond to food, stress, or medications. For a deeper look at this topic, you can find more in the LearnHub.
Overview
SLC37A4Gene function
What if the gene works
The SLC37A4 gene helps move a sugar molecule into a cell compartment called the endoplasmic reticulum. This supports blood sugar balance between meals and normal function of some infection-fighting white blood cells.
Risk
What if the gene does not work
Variants in the SLC37A4 gene can cause glycogen storage disease type Ib. People may have low blood sugar, enlarged liver, and low white blood cells with infections; milder or more severe variants can affect symptom timing and severity.
Treatment
What does that mean for your treatment
Pathogenic variants in the SLC37A4 gene guide a treatment plan that usually combines steady carbohydrate support, often uncooked cornstarch or overnight feeds, with treatment for low neutrophils when needed. Empagliflozin is now widely used in SLC37A4-related disease to improve neutrophil counts and related mouth, bowel, and infection problems. Some people still need G-CSF.
Conditions associated with SLC37A4
Gene function
What if the gene works
The SLC37A4 gene helps your cells move glucose 6 phosphate, a sugar molecule used in energy handling, into the endoplasmic reticulum, a small compartment inside the cell. There, it can be processed into free glucose for the body to use. This is a key part of the SLC37A4 gene function in everyday energy balance, especially between meals.
Inside certain cells, the SLC37A4 gene moves glucose 6 phosphate into the endoplasmic reticulum, a compartment that helps process many molecules. This step puts the sugar molecule in the right place for the next stage of glucose handling.
By placing glucose 6 phosphate where it needs to be, this gene supports the final step of making free glucose from stored carbohydrate and from newly made sugar. That helps the liver and kidneys contribute to steady blood sugar between meals.
Its protein works like a shuttle across the endoplasmic reticulum membrane, exchanging glucose 6 phosphate and phosphate. This exchange helps cells manage fuel molecules smoothly during routine energy needs.
What is a variant?
In genetics, a variant is a small difference in the DNA sequence of a gene. These differences are common and are part of normal human diversity, including variation in appearance, metabolism, and how the body responds to environmental influences. Most variants do not have any noticeable effect and simply represent natural genetic variation. Sometimes, though, a variant can more significantly change how a gene functions and may contribute to, or cause, a genetic condition.
Genetic variants
What if the gene does not work
Variants in the SLC37A4 gene can make its transporter protein unstable, misfolded, or less able to move glucose-6-phosphate into the endoplasmic reticulum (a cell compartment that processes and stores molecules). Among SLC37A4 gene variants linked to glycogen storage disease type Ib, some changes sharply reduce or fully stop transport, while milder variants may leave partial activity. That range can influence how strongly cells are affected and, in some people, how early or how prominently features appear.
How variants are linked to conditions
Pathogenic variants in the SLC37A4 gene cause glycogen storage disease type Ib, a rare inherited condition. In people with SLC37A4 gene variants linked to glycogen storage disease type Ib, doctors often see low blood sugar, an enlarged liver, slower growth, low white blood cell counts, and repeated infections. Some also develop mouth sores or bowel inflammation. This is a confirmed gene-disease relationship, not just a small change in risk.
A variant is not necessarily a diagnosis
Variants in genes are a routine part of human biology and are common throughout the general population. Most do not directly affect 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 contribute. In some situations, however, 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 SLC37A4, risk is mainly set by inheritance: a child is affected when they inherit a changed copy from both parents, so family history and both parents being carriers matter most. In people already living with this condition, long gaps without food and infections can make symptoms and complications more likely, but they do not change the underlying genetic cause.
Inheritance of SLC37A4 variants
SLC37A4-related conditions are inherited in an autosomal recessive pattern. In practical terms, the inheritance of SLC37A4 gene variants usually means a child must receive one altered copy from each parent to have the condition. Parents who each carry one variant are often unaffected themselves, and with each pregnancy there is 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 no inherited variant in this gene. Sons and daughters are affected equally.
What does my SLC37A4 result mean for my family?
For families, an SLC37A4 result usually has implications in a recessive pattern, which means parents are often healthy carriers and brothers or sisters may also be affected or be carriers. Close relatives may share the same gene change even if they have no symptoms. This can matter for family planning and for relatives who want to better understand their own chances of carrying the variant.
Genetic information
Genetic testing
How you find out about variants
To find out whether you carry a variant in the SLC37A4 gene, a lab can analyze DNA from blood, saliva, or a cheek swab. Genetic testing for SLC37A4 variants reads the gene’s sequence and looks for changes linked to glycogen storage disease type Ib. Results may show a disease causing variant, no relevant variant, or a result that needs more interpretation.
When should I consider getting a genetic test?
Consider testing the SLC37A4 gene if there is a personal or family history of glycogen storage disease type 1b, a condition that can cause low blood sugar, enlarged liver, poor growth, and frequent infections. It can also help clarify the cause when these problems begin in infancy or early childhood.
A genetic result is only one part of your health story
Genetic results can provide useful insight, but how much they reveal depends on the condition and the kind of variant present. Factors such as lifestyle, environment, age, and medical history also shape how the body functions over time. For some conditions, especially those influenced by many genes, genetic information adds context rather than certainty and is most helpful when viewed alongside other parts of care. In other situations, a genetic result can offer a clear answer. In areas like medication response, genetic findings can help put individual experiences into perspective.
Pharmacogenetics
How variants shape your response to medicine
Genetic variation can affect how your body responds to medicines. Some people break down a medication faster or slower than others, while some are more likely to get side effects or may not get the full benefit. These differences are common and are one reason the same treatment can work well for one person but less well for another. Genes are only one part of the picture, but they can play a meaningful role in how the body handles a drug.
What is Pharmacogenetics?
Pharmacogenetics examines how genetic differences affect the way people respond to medications. It looks at gene and drug patterns to help explain why the same treatment may work differently from one person to another. For many medicines, genes influence how the body processes a drug and how strong its effects may be. This information can support more informed and individualized treatment decisions. More about this topic is available in the LearnHub.
Drugs influenced by the SLC37A4 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 adjusted. Questions about medications, side effects, or other health concerns are best discussed with your doctor.
History
Throughout history, doctors described families in which children had low blood sugar, enlarged livers, and repeated infections, features now recognized as part of glycogen storage disease type Ib. In the 1970s and 1980s, researchers separated this form from closely related glycogen storage conditions because of its distinctive immune problems. From these first observations, research expanded steadily. In the late 1990s, the SLC37A4 gene was identified as the gene linked to glycogen storage disease type Ib, helping explain why some affected people had both metabolic and white blood cell findings. This discovery clarified a long-standing medical puzzle and improved genetic diagnosis for families. Over time, scientists’ understanding of the gene’s role has changed as more variants and their effects were described.