The SOD1 gene helps protect your cells from everyday “wear and tear” caused by oxygen by clearing a harmful byproduct called superoxide. The protein made by this gene helps your cells limit oxidative stress, which is especially important for long-lived cells like nerve cells. When SOD1 does not work properly, cells can be more vulnerable to damage, and certain inherited changes can cause a genetic form of amyotrophic lateral sclerosis (ALS). Public awareness of ALS grew through the Ice Bucket Challenge and public advocacy by Stephen Hawking, and SOD1 is one of the best-known genes linked to inherited ALS.
What is a gene?
A gene is a stretch of DNA that carries instructions your cells use to make molecules or manage activities in the body. Some genes provide the blueprint for proteins, which do much of the day-to-day work inside cells. Other genes mostly regulate when a process happens, where it occurs, and how much it is turned up or down. Taken together, genes affect how your body grows and operates, and they can also influence how you react to things like food, stress, or medicines. To dig deeper into this subject, you can find more information in the LearnHub.
Overview
SOD1Gene function
What if the gene works
The SOD1 gene helps protect cells from damage caused by reactive oxygen species during normal metabolism. Its protein turns superoxide into less reactive molecules, supporting healthy function in many tissues, including nerve cells.
Risk
What if the gene does not work
Harmful changes in the SOD1 gene can cause inherited amyotrophic lateral sclerosis (ALS), with worsening muscle weakness and problems with speech, swallowing, or breathing. Variant effects range from milder to severe, influencing age of onset and how quickly symptoms progress.
Treatment
What does that mean for your treatment
Certain SOD1 gene variants may make you eligible for tofersen, an antisense therapy that lowers SOD1 protein. Clinicians tailor timing and monitoring to the variant and course, and confirming the SOD1 variant can support access to care and trials.
Gene function
What if the gene works
Everyday cell activity, especially making energy, creates reactive oxygen byproducts that need to be cleared away. Across many tissues, the SOD1 gene contributes to steady, routine cell activity by helping keep these byproducts under control. This background on how the SOD1 gene works in cells explains why it matters for long-term cell health.
The SOD1 gene provides instructions for an enzyme that converts superoxide into less reactive molecules. This helps keep normal cell “exhaust” from building up during day-to-day metabolism.
By lowering reactive oxygen levels, SOD1 supports a more stable chemical environment inside cells. This helps protect many cell parts, including proteins and fats in cell membranes, during ordinary wear and tear.
The SOD1 protein uses copper and zinc to do its antioxidant job. The gene helps your cells make a protein that can hold these metals in the right way so it stays active and stable.
Some SOD1 protein is found near mitochondria, the parts of cells that generate energy. Working there helps manage reactive oxygen that is naturally produced during energy production.
What is a variant?
A genetic variant is a minor alteration in a gene’s DNA sequence. These differences occur frequently and help explain normal variation among people, such as differences in looks, metabolism, or how the body reacts to environmental factors. Many variants do not lead to any noticeable change and are part of typical genetic diversity. Sometimes, though, a variant can affect how a gene works in a more meaningful way and may play a role in, or directly cause, a genetic condition.
Genetic variants
What if the gene does not work
Changes in the SOD1 gene can alter the SOD1 protein so it misfolds or becomes unstable, which may harm motor nerve cells over time. Many SOD1 gene mutations linked to ALS act through toxic effects rather than simply reducing enzyme activity. DNA changes range from milder variants to severe mutations, and this spectrum can influence the age symptoms begin, the speed of progression, and which features are most noticeable.
How variants are linked to conditions
Some inherited changes in the SOD1 gene can cause amyotrophic lateral sclerosis (ALS), including many cases of familial ALS. In these families, a pathogenic SOD1 gene mutation can confirm the diagnosis and helps explain why weakness, muscle twitching, and trouble speaking or breathing may run in relatives. Other SOD1 variants have been studied for small effects on ALS risk, but they do not predict who will develop ALS.
A variant is not necessarily a diagnosis
Differences in DNA are a typical feature of human biology and are widespread across the population. Most genetic variants do not directly impact health and instead reflect normal variation among people. For many genes, having a variant that has been linked to a condition points to a possible connection rather than a certain diagnosis, particularly when risk is shaped by several genes along with environmental influences. In other situations, though, one well-studied variant in a particular gene can be enough to confirm a diagnosis.
Are there things that can increase or change my risk?
For people with a harmful change in the SOD1 gene, the chance of developing ALS is mostly set by that gene change, and lifestyle changes have not been proven to prevent it. Risk can still vary between families and often increases with age. There is not enough evidence to say any specific diet, supplement, or exercise plan lowers risk, but regular follow-up can support early symptom recognition and safer planning.
Inheritance of SOD1 variants
Most SOD1 gene variants linked to ALS are inherited in an autosomal dominant pattern, which means a parent with the variant can pass it to a child with a 50% chance in each pregnancy. This explains how SOD1 gene variants are inherited in many families, and the variant can come from either the mother or the father. In some families the change happens for the first time in a person, and a few specific SOD1 gene variants can follow an autosomal recessive pattern.
What does my SOD1 result mean for my family?
Seek medical advice if you have a SOD1 gene result and feel anxious about what it could mean for your children, siblings, or parents, or if your family has a history of ALS (a condition that affects nerve cells controlling muscle). A genetics professional can explain who in your family may be affected and what steps make sense next. If ALS symptoms like new muscle weakness, cramps, or twitching appear, contact a clinician promptly.
Genetic information
Genetic testing
How you find out about variants
A blood or saliva sample can be used for SOD1 genetic testing for inherited ALS, usually through DNA sequencing done in a clinical laboratory. The lab reads the SOD1 gene code and compares it with a reference to identify differences, which may be found on a targeted test or a broader ALS gene panel. Results are typically reported as pathogenic, likely pathogenic, uncertain, or benign.
When should I consider getting a genetic test?
Consider testing the SOD1 gene if you or a close relative has ALS, especially if several family members have had it or symptoms started at a younger age. Testing can also help if there is a known SOD1 gene change in your family and you want clearer information for family planning and medical decisions.
A genetic result is only one part of your health story
Genetic test results can provide useful information, but their significance varies depending on the condition and the specific type of variant found. Your health over time is also shaped by many factors, including lifestyle, environment, age, and your personal medical history. For conditions that involve many genes, genetic findings usually offer helpful background rather than a definite prediction and make the most sense when considered with the rest of your care. In some situations, though, a genetic result can be more straightforward and give a clear explanation. For topics like how you respond to certain medications, genetic information can also help put your individual experience into context.
Pharmacogenetics
How variants shape your response to medicine
Some variants in the SOD1 gene can matter for medication because certain newer, targeted treatments for a specific type of amyotrophic lateral sclerosis (ALS) are designed for people whose ALS is linked to a SOD1 gene change. More broadly, genetic differences help explain why the same medicine can work well for one person but cause more side effects or less benefit for another. Gene variants can influence how quickly your body processes a drug, how strongly a drug acts in its target tissues, or how sensitive you are to certain adverse effects. This kind of variation is common, so medication response is often a mix of genetics plus factors like age, other health conditions, and other medicines you take.
What is Pharmacogenetics?
Pharmacogenetics focuses on how variations in your genes can affect the way you respond to medications. By examining relationships between specific genes and particular drugs, it aims to explain why the same treatment can have different effects in different people. With many medicines, genetics can influence how powerfully a drug works and how your body breaks it down. This information can support treatment choices that are more informed and tailored to the individual. More detailed information on this subject is available in the LearnHub.
Drugs influenced by the SOD1 gene
When should I seek medical advice?
Seek medical advice if ALS has occurred in your family and the SOD1 gene has been mentioned, especially if you’re anxious or already under care for nerve or muscle symptoms. Get checked promptly for persistent muscle weakness, twitching, cramps, slurred speech, trouble swallowing, or shortness of breath.
History
Researchers first linked changes in the SOD1 gene to inherited amyotrophic lateral sclerosis (ALS) in 1993, marking the first time a specific gene was clearly tied to ALS in families. In recent decades, awareness of this gene’s role has grown as genetic testing made it possible to identify some familial ALS cases more precisely. The discovery helped shift ALS research toward genetic causes and opened the door to studying how different inherited changes can lead to different patterns of illness within families. SOD1 findings also supported the development of widely used laboratory models of ALS, which sped up research worldwide. Over time, larger international studies clarified that SOD1 is one of several genes that can contribute to inherited ALS, rather than explaining all ALS cases.