The SCARB1 gene helps your body handle cholesterol by allowing cells to take up cholesterol carried in HDL, often called “good” cholesterol. This gene plays an important role in keeping cholesterol available for the liver and for making hormones. If the gene does not work well, HDL levels in the blood can rise while cholesterol movement through the body becomes less efficient. Some SCARB1 variants are linked to differences in heart disease risk and, in some people, fertility or hormone related effects.
What is a gene?
Genes are stretches of DNA that hold instructions your cells use to make molecules or direct processes in the body. Some genes contain the information needed to build proteins, the parts of cells that do much of the work. Others mainly help determine when certain processes happen, where they happen, and how active they are. Taken together, genes influence how the body develops and functions, and they can affect how you respond to food, stress, or medicines. For a deeper look at this topic, you can learn more in the LearnHub.
Overview
SCARB1Gene function
What if the gene works
The SCARB1 gene helps cells take in cholesterol from HDL, often called good cholesterol. This supports cholesterol balance in the liver and helps the body make steroid hormones.
Risk
What if the gene does not work
Variants in the SCARB1 gene can range from milder to more severe. Reduced SCARB1 function means cells take up less cholesterol from HDL, changing cholesterol handling in the liver, steroid-producing glands, and other tissues.
Treatment
What does that mean for your treatment
No treatment or drug choice is currently guided by a pathogenic or loss-of-function variant in the SCARB1 gene under current clinical guidelines. The SCARB1 gene is being studied as a marker and possible drug target in cholesterol handling and cardiovascular disease, but this has not changed routine care.
Gene function
What if the gene works
Many cells use the SCARB1 gene to move cholesterol in a controlled way. Its protein sits on the cell surface and works closely with HDL, often called good cholesterol. This helps explain how your body handles good cholesterol for everyday needs such as cell membranes, bile, and other routine cell tasks.
SCARB1 makes a surface protein that binds HDL at the outside of the cell. This lets the cell draw in cholesterol from HDL without taking in the whole HDL particle.
Its protein helps cholesterol move between cells and HDL in either direction, depending on what the cell needs. This helps keep a balanced supply for membranes and other routine cell work.
In the liver, SCARB1 helps collect cholesterol carried by HDL so it can be reused or released into bile. This supports the body's normal cholesterol recycling and clearing pathway.
What is a variant?
A genetic variant is a small difference in the DNA sequence within a gene. These changes are common and help explain normal human diversity, such as differences in appearance, metabolism, or the way the body responds to environmental influences. Many variants do not have any noticeable effect and are simply part of natural genetic variation. In some situations, though, a variant can change a gene’s function more substantially and may contribute to or cause a genetic condition.
Genetic variants
What if the gene does not work
Variants in the SCARB1 gene can change how much of its cell surface protein reaches the membrane and how well it interacts with HDL particles. Some milder changes only partly reduce selective cholesterol uptake, while more severe variants can disrupt protein folding, stability, or trafficking inside the cell. This helps explain how SCARB1 gene variants affect cholesterol transport at the cellular level.
How variants are linked to conditions
Research on how SCARB1 gene variants affect cholesterol and heart disease risk shows that common changes are linked to differences in HDL cholesterol, often called “good” cholesterol. Some rare variants in the SCARB1 gene have also been associated with very high HDL levels and, in some studies, a higher risk of coronary artery disease. These findings describe tendencies in groups of people and do not mean that a person with a SCARB1 variant will develop heart disease.
A variant is not necessarily a diagnosis
Variants in genes are a routine feature of human biology and are widely seen across the general population. Most do not directly affect health and instead represent normal human variation. For many genes, having a variant associated with a condition points to a possible link rather than a firm diagnosis, particularly when several genes and environmental influences also play a role. In some situations, though, one well understood variant in a particular gene is enough to confirm the diagnosis.
Are there things that can increase or change my risk?
For people with SCARB1 changes, the chance of heart and blood vessel disease can also be shaped by everyday factors such as smoking, high blood pressure, diabetes, body weight, diet, and physical activity. Family history and other cholesterol-related genes can matter too, so SCARB1 is only one part of the overall risk picture.
Inheritance of SCARB1 variants
There is not yet a broadly confirmed, disease-specific Mendelian pattern for how SCARB1 gene variants are inherited, because most well-known SCARB1 findings relate to cholesterol traits and heart disease risk rather than one clearly defined inherited condition. In practice, how SCARB1 gene variants are inherited follows the usual family pattern for a gene on an autosome: you receive one copy from each parent. The SCARB1 gene is located on chromosome 12, so inheritance does not differ between males and females in the way it can for genes on the X or Y chromosome.
What does my SCARB1 result mean for my family?
There is not yet a broadly confirmed inheritance pattern tied to a specific, well-defined inherited condition for the SCARB1 gene, though this can change as research grows. If you have a specific SCARB1 result and want to understand what it could mean for close relatives, a doctor or genetic counselor can help interpret it in the context of your family history and cholesterol findings.
Genetic information
Genetic testing
How you find out about variants
To find out whether you carry a variant in the SCARB1 gene, genetic testing for SCARB1 variants reads the DNA from a blood sample, saliva sample, or cheek swab and looks for changes in the gene's code. Results can show whether a variant is present, absent, or of uncertain significance.
When should I consider getting a genetic test?
There is not yet a broadly established reason for most people to get genetic testing just for the SCARB1 gene. If you have very unusual cholesterol results or a strong family history of early heart disease, testing decisions are best made with a doctor or genetic counselor.
A genetic result is only one part of your health story
A genetic result can provide useful insight, but how much it explains varies depending on the condition and the type of variant involved. Many factors, including lifestyle, environment, age, and medical history, also affect how the body functions over time. For some conditions, especially those shaped by many genes, genetic information provides context rather than certainty and is best interpreted alongside 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 make sense of individual experiences.
Pharmacogenetics
How variants shape your response to medicine
Genetic variation can affect how people respond to medicines. A treatment that works well for one person may work less well for another, or may cause more side effects, because the body can absorb, break down, move, or respond to a drug differently. These inherited differences are common and are one reason medication response is not the same for everyone. In some cases, this can influence how well a treatment works or how sensitive someone is to it.
What is Pharmacogenetics?
Pharmacogenetics focuses on how genetic differences can affect a person’s response to medications. By examining the relationship between genes and drugs, it helps explain why the same treatment may work differently from one person to another. For many medicines, genes can influence both how strongly a drug works and how the body handles it. This understanding can support more informed and personalized treatment decisions. You can read more about this topic in the LearnHub.
Drugs influenced by the SCARB1 gene
When should I seek medical advice?
There is not yet a broadly confirmed role for this gene in guiding medication choices. Questions about medicines, side effects, or cholesterol-related health concerns are best discussed with your doctor. Researchers have studied SCARB1 for possible links to response to some cholesterol-lowering medicines, but this is not part of routine care.
History
Research on cholesterol transport set the stage for the discovery of the SCARB1 gene in the 1990s, when scientists were mapping how the body handles blood fats. The gene was identified during efforts to understand why cholesterol moves differently in the liver, adrenal glands, and other tissues. Initially understood only through visible traits, later recognized as tied to a specific gene, this line of work helped connect older cholesterol research with modern human genetics. Interest in the SCARB1 gene grew again when population studies linked certain variants to unusual HDL cholesterol levels, sometimes called “good” cholesterol. These findings drew attention because they showed that higher HDL levels do not always translate into the heart protection once assumed. Over time, descriptions became more precise as large genetic studies refined the picture.