The SORD gene helps your body break down sorbitol, a natural sugar alcohol, so it does not build up in nerves. This gene plays an important role in keeping peripheral nerves working properly. If it does not work well, sorbitol can collect and damage these nerves, often causing slowly worsening weakness in the feet and lower legs, foot drop, cramps, and sometimes numbness. People with pathogenic variants in both copies of the SORD gene may be diagnosed with an inherited neuropathy such as distal hereditary motor neuropathy or Charcot-Marie-Tooth disease.
What is a gene?
Genes are stretches of DNA that hold instructions cells use to make molecules or regulate activities in the body. Some genes provide the code for proteins, which are the parts of cells that do much of the work. Others mainly direct when, where, and how much certain activities take place. Taken together, genes affect how the body develops and functions, and they can influence your response to food, stress, and medications. For a deeper look at this topic, you can find more in the LearnHub.
Overview
SORDGene function
What if the gene works
The SORD gene helps cells break down sorbitol, a sugar alcohol, into fructose. This supports normal sugar handling and helps limit sorbitol buildup inside cells.
Risk
What if the gene does not work
When both copies of the SORD gene do not work, an inherited nerve condition can cause foot drop, leg weakness, and trouble walking. Milder or more severe variants may change when symptoms start and how much weakness develops.
Treatment
What does that mean for your treatment
For people with pathogenic variants in both copies of the SORD gene, no treatment or management approach specific to the SORD gene is currently established in clinical guidelines. Research is underway on aldose reductase inhibitors, which aim to lower sorbitol buildup in neuropathy linked to the SORD gene.
Gene function
What if the gene works
Seeing what the SORD gene does in daily metabolism helps explain how your body handles several forms of sugar, not just glucose. One routine step is changing sorbitol, a sugar alcohol, into fructose. This helps cells manage sugar processing from day to day.
The SORD gene gives cells instructions for an enzyme that turns sorbitol, a sugar alcohol, into fructose. This is a routine step in how your body processes certain sugars.
This conversion helps keep sorbitol and fructose in balance inside cells. It supports steady sugar handling in many tissues during everyday metabolism.
The fructose made through this step can then join broader energy pathways in the body. That makes the SORD gene part of normal carbohydrate metabolism.
What is a variant?
A genetic variant is a minor change in the DNA sequence of a gene. These changes are common and are part of normal human diversity, including differences in appearance, metabolism, and how the body responds to environmental influences. Many variants do not have any noticeable effect and simply represent natural genetic variation. Sometimes, though, a variant changes how a gene works more significantly and can contribute to or cause a genetic condition.
Genetic variants
What if the gene does not work
In people with SORD-related neuropathy, variants in the SORD gene usually reduce or shut down the enzyme, so cells clear sorbitol poorly and it builds up, especially in nerve cells. Many shorten the protein or make it unstable, which can leave very little activity. Milder variants may preserve some activity, while more severe variants can remove it almost completely. This helps explain how SORD gene variants affect nerve cells, including when symptoms start and how marked they become.
How variants are linked to conditions
Pathogenic variants in the SORD gene cause an inherited peripheral neuropathy, most often distal hereditary motor neuropathy or axonal Charcot-Marie-Tooth disease. In plain terms, the link between SORD gene variants and neuropathy usually involves gradually increasing weakness in the feet and lower legs, sometimes with muscle cramps, balance problems, or mild numbness. This condition is typically autosomal recessive, so the diagnosis is usually confirmed when both copies of the gene carry disease-causing variants.
A variant is not necessarily a diagnosis
Genetic variants are a usual part of human biology and are widely found across the general population. Most do not directly affect health and simply contribute to normal human diversity. For many genes, having a variant associated with a condition points to a possible link rather than a certain diagnosis, particularly when several genes and environmental influences play a role. 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 SORD, risk is mainly shaped by inheritance: the condition usually develops when someone is born with changes in both copies of the SORD gene, while carrying one changed copy usually does not cause symptoms. There is not yet broadly confirmed evidence that lifestyle or environmental factors meaningfully increase or lower this genetic risk.
Inheritance of SORD variants
For families asking about the inheritance of the SORD gene variants, the well-established pattern is autosomal recessive. This means a person usually inherits one altered copy of the SORD gene from each parent, and parents who carry one variant typically do not have symptoms. When both parents are carriers, each pregnancy has a 25% chance of a child inheriting both altered copies, a 50% chance of being a carrier, and a 25% chance of inheriting neither variant. Because the SORD gene is on chromosome 15, which is an autosome, this pattern is the same for males and females.
What does my SORD result mean for my family?
For SORD-related nerve conditions, family members are usually affected only if they inherited a changed copy from both parents. Brothers and sisters of someone with a confirmed SORD-related condition may also be affected or may be carriers, while parents are usually healthy carriers. Other relatives may also carry a changed SORD copy, so the meaning for family members often centers on carrier status and whether the condition is already present in close relatives.
Genetic information
Genetic testing
How you find out about variants
SORD genetic testing looks for changes in the SORD gene, usually from a blood or saliva sample. A lab reads the gene’s DNA code to see whether you carry a variant, including two changed copies that can confirm SORD-related neuropathy in the right clinical setting.
When should I consider getting a genetic test?
Consider testing the SORD gene if there is unexplained inherited nerve disease in the family, especially slowly worsening weakness in the feet or legs, foot drop, high arches, or numbness. It can also help clarify the cause when these symptoms start in childhood, the teen years, or adulthood without another clear explanation.
A genetic result is only one part of your health story
A genetic result can provide useful insight, but the amount it reveals varies with the condition and the kind of variant involved. How the body functions over time is also shaped by many factors, including lifestyle, environment, age, and medical history. For some conditions, particularly those affected by many genes, genetic information offers context rather than certainty and is most helpful 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 also help put individual experiences in context.
Pharmacogenetics
How variants shape your response to medicine
Genetic variation can affect how your body handles medicines, so the same treatment may not work the same way for everyone. Some people break down a drug faster or slower, while others are more or less sensitive to its effects. This can influence how well a medicine works or how likely side effects are. Medication response also depends on factors like age, liver and kidney function, and other medicines, so genes are one part of the picture.
What is Pharmacogenetics?
Pharmacogenetics is the area of study that examines how genetic differences affect medication response. It focuses on the links between genes and drugs to help explain why the same treatment may work differently from one person to another. For many medicines, genes can influence how strongly a drug works or how the body processes it. This information can help support more informed, individualized treatment decisions. If you want to look into this subject more closely, you can learn more in the LearnHub.
Drugs influenced by the SORD gene
When should I seek medical advice?
There is not yet a broadly confirmed role for this gene in guiding medicine choices or dosing. If you have concerns about side effects, how well a treatment is working, or possible interactions with other health conditions, talk with your doctor or pharmacist.
History
SORD first drew scientific interest through studies of sugar metabolism in the mid 20th century, when researchers identified the enzyme later linked to this gene. The SORD gene itself was characterized as human gene mapping improved in the late 20th century. In recent decades, awareness of this gene’s role has grown. A major turning point came in 2020, when researchers showed that inherited SORD variants are a relatively common cause of certain hereditary nerve conditions affecting movement and sensation. From these first observations, research expanded steadily, and SORD shifted from being mainly a laboratory gene of metabolic interest to one with clear importance in clinical genetics.