The BRAF gene gives cells instructions for a protein that passes growth signals, helping cells divide at the right time. If it does not work normally, cells may keep growing when they should stop, so certain BRAF variants are linked to cancers such as melanoma, thyroid cancer, and some colon and lung cancers. This gene became more widely known as BRAF testing and targeted treatment changed care for some people with melanoma. In cancer care, a BRAF result can help show whether a tumor may respond to certain medicines.
What is a gene?
Genes are stretches of DNA that carry instructions your cells use to make molecules or manage processes in the body. Some genes provide the directions for building proteins, which are the parts of cells that do much of the work. Others mainly regulate when, where, and how strongly certain activities take place. Together, genes affect how the body develops and works, and they can influence how you respond to food, stress, or medications. More information on this topic is available in the LearnHub.
Overview
BRAFGene function
What if the gene works
Your cells rely on the BRAF gene to pass growth signals inward. This helps control when cells grow, divide, mature, and survive.
Risk
What if the gene does not work
Changes in the BRAF gene can overactivate cell growth signals. Milder or more severe variants may cause cardiofaciocutaneous syndrome, with developmental, heart, skin, and facial differences, or can drive several cancers when they arise only in tumor cells.
Treatment
What does that mean for your treatment
A pathogenic variant in the BRAF gene can make targeted treatment relevant, especially with BRAF V600E or similar V600 variants. Care may include a BRAF inhibitor, often together with a MEK inhibitor, because this usually improves control and reduces some treatment related problems. In colorectal cancer, BRAF targeted therapy is typically combined with an EGFR blocking drug rather than used alone.
Conditions associated with BRAF
Gene function
What if the gene works
Understanding BRAF gene function makes it easier to see how cells respond to everyday growth signals. The BRAF gene helps pass messages inside cells so they know when to grow, divide, or take on a more specialized job. This supports steady tissue renewal throughout life.
The BRAF gene acts as part of a cell messaging pathway that carries signals from the cell surface inward. Its protein passes the message along in a stepwise chain, helping cells respond in an organized way.
One of the BRAF gene’s main jobs is helping control when cells move into growth and division. This gives tissues a more coordinated pattern for routine repair and renewal.
The BRAF gene also helps guide how immature cells develop into more specialized cell types. This role is especially important during early development and continues to support normal tissue function later in life.
What is a variant?
A genetic variant is a small difference in the DNA sequence within a gene. These differences are common and help shape normal human diversity, including variation in appearance, metabolism, and the way the body responds to environmental influences. Many variants do not cause any noticeable effect and are simply part of natural genetic variation. Sometimes, though, a variant changes how a gene works more substantially and can contribute to or cause a genetic condition.
Genetic variants
What if the gene does not work
Variants in the BRAF gene can make the BRAF protein overactive, less active, or less stable, changing MAPK signaling, a cell pathway. Some variants, including BRAF V600E, keep the protein switched on, while others have milder effects on activity or on how the protein binds its partners. This range helps explain how BRAF gene variants affect protein function and why stronger activating variants are often seen in cancer, while milder inherited variants can lead to more variable developmental features.
How variants are linked to conditions
Pathogenic variants in the BRAF gene can cause cardiofaciocutaneous syndrome, which often includes heart differences, characteristic facial features, skin and hair changes, and developmental delay. In cancer care, doctors often look for BRAF gene variants linked to melanoma, papillary thyroid cancer, colorectal cancer, some lung cancers, and hairy cell leukemia, usually as changes found in tumor cells rather than inherited changes. These variants help classify a tumor and may guide treatment, but they do not mean relatives will develop cancer.
A variant is not necessarily a diagnosis
Genetic variants are a usual part of human biology and are common throughout the general population. Most do not have a direct effect on health and simply reflect natural human diversity. For many genes, carrying a variant associated with a condition suggests a possible link rather than a definite diagnosis, especially when multiple genes and environmental factors are involved. In some situations, however, a single well described variant in a specific gene can be enough to confirm a diagnosis.
Are there things that can increase or change my risk?
There is not yet broad, disease-specific evidence that particular lifestyle or environmental factors clearly increase or reduce risk related to the BRAF gene itself. Risk can vary a lot depending on whether a BRAF change is inherited or found only in tumor cells, and for cancers, other genes and exposures also matter.
Inheritance of BRAF variants
For families asking how BRAF gene variants are inherited, the best-established pattern is autosomal dominant for inherited BRAF-related conditions such as cardiofaciocutaneous syndrome. This means a person needs one altered copy of the BRAF gene to have the condition, and an affected parent can pass it to each child with a 50% chance. Many people with a disease-causing variant in the BRAF gene have a new (de novo) variant that was not inherited from either parent. Sons and daughters are affected and can inherit it equally.
What does my BRAF result mean for my family?
For an inherited BRAF-related condition such as cardiofaciocutaneous syndrome, close family members may also want to learn whether they carry the same gene change. This kind of result is usually passed in a dominant way, so a parent, brother, sister, or child could sometimes share it, but many cases happen for the first time in the affected family member and are not inherited from either parent. A BRAF change found only in a tumor usually does not have the same meaning for relatives.
Genetic information
Genetic testing
How you find out about variants
To look for variants in the BRAF gene, labs use BRAF genetic testing on a blood, saliva, or tumor sample. The test reads the DNA sequence to check for known variants, and the sample type helps show whether a variant is inherited or found only in the tumor.
When should I consider getting a genetic test?
BRAF testing may be considered if a child has a pattern of heart, skin, face, and growth differences that suggests cardiofaciocutaneous syndrome, an inherited condition linked to this gene. In cancer care, testing a tumor for BRAF changes can also help guide treatment choices.
A genetic result is only one part of your health story
A genetic finding can provide useful information, but how much it explains depends on the condition and on the type of variant involved. Over time, many factors, including lifestyle, environment, age, and medical history, influence how the body functions. For some conditions, especially those shaped by many genes, genetic information offers context rather than certainty and is best understood together with other parts of care. In other situations, a genetic result can give a clear answer. In areas such as medication response, genetic results may help place individual experiences in context.
Pharmacogenetics
How variants shape your response to medicine
Variants in the BRAF gene, especially BRAF V600 changes found in cancer cells, can help predict whether certain targeted cancer medicines are likely to work. When a treatment is designed to block an overactive BRAF signal, people whose cancer carries one of these variants may be more likely to benefit, while others may not respond the same way. More broadly, genetic differences are one reason the same medicine can work differently from one person to another. They can affect how strongly a treatment works or how sensitive someone is to side effects.
What is Pharmacogenetics?
Pharmacogenetics examines the ways genetic differences shape a person’s response to medications. By studying links between genes and drugs, it helps explain why the same treatment can work differently in different people. With many medicines, genes influence either how strongly a drug works or how the body handles it. This information can support treatment decisions that are both more informed and more individualized. More on this topic is available in the LearnHub.
Drugs influenced by the BRAF gene
When should I seek medical advice?
There is not a broadly confirmed inherited medication-response role for this gene, so general questions about medicines are best discussed with your doctor. In cancer care, though, BRAF changes found in the tumor can help guide the use of certain targeted treatments, so this is worth discussing with your cancer team if BRAF-related cancer treatment is being considered.
History
The BRAF gene entered cancer research in the early 2000s, when scientists identified it as a key cancer related gene in several human tumors. Its name comes from the RAF family, first linked to cancer through earlier studies of viral genes and fast growing fibrosarcoma cells. From these first observations, research expanded steadily. A major turning point came in 2002, when the BRAF V600E variant was reported in melanoma, drawing wide attention across cancer medicine. That finding helped open the way for targeted treatments designed for people whose tumors carry this variant. Over time, the BRAF gene became one of the best known examples of how genetic discoveries can reshape cancer diagnosis and treatment.