The FLT3 gene helps control the growth and survival of early blood cells, especially in the bone marrow. If this gene does not work normally and becomes too active, immature white blood cells may keep multiplying when they should stop. Some variants in the FLT3 gene are linked to acute myeloid leukemia and can influence how the condition behaves and how treatment is planned. FLT3 is mainly known in leukemia care and research rather than through celebrity or media attention.
What is a gene?
Genes are sections of DNA that carry instructions your cells use to make molecules or regulate processes throughout the body. Some genes provide the directions for producing proteins, which do much of the cell’s work. Others mainly guide when certain processes happen, where they happen, and how active they are. Taken together, genes affect how your body develops and functions, and they can influence how you respond to food, stress, or medications. For a deeper look at this topic, visit the LearnHub.
Overview
FLT3Gene function
What if the gene works
The FLT3 gene helps control how early blood cells grow, survive, and mature. It is especially active in the bone marrow, where it supports normal blood and immune cell development.
Risk
What if the gene does not work
Changes in the FLT3 gene are best known in acute myeloid leukemia, where they can drive abnormal blood cell growth. Less disruptive and more disruptive variants may influence how early leukemia appears and how aggressive it becomes.
Treatment
What does that mean for your treatment
Pathogenic variants in the FLT3 gene can make FLT3 inhibitor medicines part of treatment planning. In current guidelines, this often includes midostaurin with initial therapy and gilteritinib when the condition returns or does not respond. These variants can also support closer monitoring after treatment.
Conditions associated with FLT3
Gene function
What if the gene works
In bone marrow, the FLT3 gene helps early blood cells respond to growth cues. Its protein sits on the cell surface and passes outside messages inward. This supports the steady development of new blood cells, especially in the early stages. Understanding this role helps explain how the FLT3 gene supports blood cell growth and development.
The FLT3 gene makes a receptor, a protein that receives growth signals at the cell surface. When a matching signal reaches the cell, the receptor passes that message inward.
This signaling helps early blood-forming cells grow and divide in a controlled way. It supports the ongoing supply of developing blood cells in the bone marrow.
The FLT3 gene also helps young blood cells stay alive while they are developing. This gives them time to respond to normal growth cues and continue maturing.
FLT3 signaling helps guide some immature blood cells as they move toward more specialized roles. This is especially important for early cells that will become parts of the immune system.
What is a variant?
A genetic variant is a minor difference in the DNA sequence of a gene. These differences are common and help account for normal human diversity, including differences in appearance, metabolism, or how the body responds to environmental influences. Many variants do not lead to any noticeable effect and are simply part of natural genetic variation. In some situations, though, a variant can change how a gene functions more substantially and may contribute to or cause a genetic condition.
Genetic variants
What if the gene does not work
Certain variants in the FLT3 gene keep its growth signal stuck in the "on" position, especially internal tandem duplication variants (an extra copied stretch of DNA) and changes in the signaling region. This helps explain how FLT3 gene variants affect cell signaling and why some changes activate the gene more strongly than others. More strongly activating variants are linked to faster leukemia cell growth and may be tied to earlier or harder-to-control acute myeloid leukemia.
How variants are linked to conditions
Variants in the FLT3 gene are most strongly linked to acute myeloid leukemia, and FLT3 gene variants in acute myeloid leukemia can help doctors understand the leukemia’s behavior. Certain acquired variants, especially FLT3-ITD and some FLT3 TKD variants, are associated with a higher chance that AML may be more active or return after treatment. FLT3 variants are also found in some other blood cancers, but the clearest and most widely accepted link is with AML.
A variant is not necessarily a diagnosis
Genetic variants are a usual part of human biology and are common across the general population. Most do not directly affect health and simply reflect natural human diversity. For many genes, carrying a variant associated with a condition indicates a possible link rather than a definite diagnosis, especially when more than one gene and environmental factors are involved. 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?
There is not yet broadly confirmed evidence on specific day-to-day factors that increase or reduce risk related to the FLT3 gene itself. People with questions about their personal risk, especially around blood cancers such as acute myeloid leukemia, can speak with a doctor or genetic counselor.
Inheritance of FLT3 variants
There is not yet a broadly confirmed inherited disease pattern for the FLT3 gene, because most clinically important FLT3 changes are found only in blood cancer cells and are not passed through families. In practical terms, when people ask how FLT3 gene variants are inherited, the answer is usually that the common leukemia related variants are acquired during life rather than inherited from a parent. The FLT3 gene is located on chromosome 13, which is an autosome, so each person normally inherits one copy from each parent.
What does my FLT3 result mean for my family?
There isn't yet a broadly confirmed family inheritance pattern tied to a specific condition for FLT3. Most FLT3 results are found in blood cancer cells during the illness rather than being inherited, so what a FLT3 result means for relatives depends on the exact kind of result.
Genetic information
Genetic testing
How you find out about variants
FLT3 genetic testing in acute myeloid leukemia usually checks a blood or bone marrow sample for variants in the FLT3 gene. A lab examines DNA from leukemia cells to see whether a clinically relevant FLT3 variant is present. Results show whether this gene change was found and can help shape treatment decisions.
When should I consider getting a genetic test?
FLT3 testing is usually considered if someone has acute myeloid leukemia, because changes in this gene in leukemia cells can affect outlook and treatment choices. It may also be checked again if the leukemia comes back. This test is usually done on blood or bone marrow cancer cells, not as an inherited family test.
A genetic result is only one part of your health story
A genetic finding can provide useful insight, but how much it reveals depends on the condition and the kind of variant involved. Over time, many factors shape how the body functions, including lifestyle, environment, age, and medical history. In some conditions, especially those influenced by many genes, genetic information offers context rather than certainty and is best considered along 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 into context.
Pharmacogenetics
How variants shape your response to medicine
Genetic variation can affect how your body responds to some medicines, so the same treatment may work differently from one person to another. These differences can change how quickly a drug is processed, how strongly it works, or how sensitive someone is to side effects. This is a common part of normal human variation and helps explain why medication response is not the same for everyone. Genetics is only one part of the picture, alongside factors like age, overall health, and other medicines.
What is Pharmacogenetics?
Pharmacogenetics is the area of medicine that examines how genetic differences shape a person’s response to medications. It studies gene drug patterns to help explain why the same treatment can affect people in different ways. With many medicines, genes influence how the body handles a drug and how strong its effects are. This information can support treatment choices that are more informed and more individualized. More detail on this topic is available in the LearnHub.
Drugs influenced by the FLT3 gene
When should I seek medical advice?
There is not yet a broadly confirmed role for this gene in routine medication response across general medical care, so general questions about medicines or side effects are best discussed with your doctor. In a fast-growing blood cancer called acute myeloid leukemia, FLT3 changes in the cancer cells can help guide some targeted treatment choices, so people living with this cancer should speak with their cancer team before treatment starts or changes.
History
The FLT3 gene entered medical research in the early 1990s, when scientists identified it as a new receptor gene active in blood-forming cells. Soon after, researchers linked changes in the FLT3 gene to acute myeloid leukemia, especially a type of internal duplication that became one of the most studied genetic findings in this cancer. From these first observations, research expanded steadily. By the 2000s, FLT3 testing was becoming part of leukemia workups because it could help classify disease and guide research decisions. Its history also shaped cancer treatment, as drug development began focusing on FLT3 targeted medicines. Today, the FLT3 gene is a well-known example of how genetic discoveries can move from the lab into everyday leukemia care.