The SALL1 gene helps control how several body parts form before birth by guiding when other genes turn on and off. If it does not work properly, a person may have Townes-Brocks syndrome, which can affect the ears, thumbs, anus, kidneys, and sometimes hearing or heart health. Most people learn about the SALL1 gene through genetic testing after birth differences or hearing loss are found in a child or across a family.
What is a gene?
Genes are stretches of DNA that carry 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 the work. Others are used mainly to direct when certain activities happen, where they take place, and how active they are. In combination, genes affect how the body grows and works, and they can influence your response to food, stress, and medicines. For a more detailed overview, see the LearnHub.
Overview
SALL1Gene function
What if the gene works
The SALL1 gene helps control other genes during early growth. It is especially important for forming the kidneys, hands, ears, and other body structures before birth.
Risk
What if the gene does not work
Variants in the SALL1 gene most often cause Townes-Brocks syndrome, which can affect the ears, thumbs, anus, kidneys, and hearing. Effects can range from mild to more marked, and different variants may shape which features appear.
Treatment
What does that mean for your treatment
No treatment or drug selection approach specific to the SALL1 gene is currently established. Care is guided by the person’s features, such as hearing, kidney, limb, or anal concerns, rather than by a medicine chosen for the SALL1 gene itself.
Conditions associated with SALL1
Gene function
What if the gene works
The SALL1 gene helps guide early body development by controlling when other genes are active. It is especially important while organs and body structures are taking shape before birth. Understanding what the SALL1 gene does in the body helps explain how cells follow the right building plan from the start.
Inside the cell nucleus, the SALL1 gene helps turn groups of other genes on or off at the right time. This gives developing cells clear instructions as they grow and specialize.
The SALL1 gene supports the body’s early layout, helping cells know where structures should form during development. This steady patterning helps shape organs and body parts in an organized way.
During early development, this gene helps guide the formation of several structures, including the kidneys, limbs, and parts of the ears. It supports coordinated growth so tissues develop in the right place and at the right stage.
SALL1 activity helps developing cells stay on the right path as they mature into different tissue types. This kind of gene control supports stable, step by step growth before birth.
What is a variant?
Genetic variants are small differences in the DNA sequence within a gene. They are common and help explain normal variation among people, including differences in appearance, metabolism, and the way the body responds to environmental influences. Many do not cause any noticeable effect and are simply part of natural genetic variation. Some variants, however, can change how a gene works more substantially and may contribute to or cause a genetic condition.
Genetic variants
What if the gene does not work
Variants in the SALL1 gene often change the instructions so the cell makes a shortened protein that can disrupt the normal protein from the other gene copy. This helps explain how SALL1 gene variants affect protein function in Townes-Brocks syndrome. Some changes mainly reduce the amount of working protein, while others have a stronger blocking effect, so the impact can range from milder to more marked and may influence which features appear and how early they start.
How variants are linked to conditions
Pathogenic variants in the SALL1 gene cause Townes-Brocks syndrome, a genetic condition linked with differences affecting the ears, thumbs, anus, kidneys, and hearing. The link between SALL1 gene variants and Townes-Brocks syndrome is well established. Some people also have foot differences, heart findings, or developmental delays. Features can vary a lot from one person to another, even within the same family.
A variant is not necessarily a diagnosis
Variants are a routine feature of human biology and are widely found in the general population. Most do not have a direct effect on health and instead reflect normal human variation. For many genes, carrying a variant tied to a condition indicates a possible association rather than a certain diagnosis, especially when multiple genes and environmental factors both play a part. In some situations, though, a single well characterized variant in a specific gene can be enough to confirm a diagnosis.
Are there things that can increase or change my risk?
For SALL1, risk is mainly determined by whether you carry a disease-causing variant, which is often inherited from a parent but can also happen for the first time in a child. There is not enough evidence to say that diet, exercise, or other lifestyle changes lower the chance of developing a SALL1-related condition.
Inheritance of SALL1 variants
SALL1-related conditions are usually inherited in an autosomal dominant pattern, which means one altered copy of the SALL1 gene can be enough to cause the condition. In families, a parent with a disease-causing SALL1 variant has a 50% chance of passing it on in each pregnancy. How SALL1 variants are inherited can also include new, de novo changes, meaning the variant starts in the child and was not inherited from either parent. Once a de novo SALL1 variant is present, it can be passed to future children in the same autosomal dominant way.
What does my SALL1 result mean for my family?
Changes in the SALL1 gene are best known for causing Townes-Brocks syndrome, which usually runs in families in a dominant pattern. This means close relatives, such as a parent, brother, sister, or child, may also carry the same gene change and may have similar features, even if those features are mild. Some cases happen for the first time in one person, so a parent does not always have the change.
Genetic information
Genetic testing
How you find out about variants
Genetic testing for SALL1 variants usually uses a blood or saliva sample to read the SALL1 gene and look for changes linked to inherited conditions. A lab compares your DNA sequence with the usual sequence and reports whether a variant was found, and if so, whether it is known to explain symptoms or family history.
When should I consider getting a genetic test?
Genetic testing for SALL1 may be worth discussing if you or your child has a pattern of birth differences such as unusual thumbs, ear differences or hearing loss, kidney problems, or a problem with the anal opening, especially when these run in the family. A confirmed SALL1 change can help explain the diagnosis and guide family testing.
A genetic result is only one part of your health story
A genetic result can give helpful insight, but what it reveals depends on the condition and the specific type of variant. Many other factors also affect how the body functions over time, including lifestyle, environment, age, and medical history. In some conditions, especially those shaped by many genes, genetic information provides context rather than certainty and is most useful when viewed together with other parts of care. In other situations, a genetic result can offer a clear answer. In areas like 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. Some people break down a drug faster or slower than others, so the same treatment may work better, work less well, or cause more side effects. These differences are common and are one reason medication response can vary from person to person.
What is Pharmacogenetics?
Pharmacogenetics is the study of how differences in genes can affect the way people respond to medicines. It examines gene and drug patterns to better explain why the same treatment may work differently from one person to another. For many medications, genes can influence how strongly a medicine works or how the body handles it. This information can support more informed, more personalized treatment decisions. To explore this topic further, you can learn more in the LearnHub.
Drugs influenced by the SALL1 gene
When should I seek medical advice?
There is not yet a broadly confirmed role for this gene in predicting how you will respond to medicines, so questions about side effects, new symptoms, or treatment changes are best discussed with your doctor.
History
SALL1 entered medical genetics through the study of Townes-Brocks syndrome, a condition first described in 1972 by physicians Philip Townes and Eric Brocks. Initially understood only through visible traits, later recognized as tied to a specific gene, the SALL1 gene was identified in the late 1990s as the main cause in many affected families. This discovery helped connect a recognizable pattern of birth differences with a clear inherited cause. From these first observations, research expanded steadily and showed that different variants in the SALL1 gene can lead to a range of features, even within the same family. That work made SALL1 an important part of the history of developmental genetics and inherited conditions affecting several body systems.