The FLVCR2 gene helps move heme, an iron carrying molecule that cells use, across cell membranes and supports early brain and blood vessel development. This gene plays an important role in how tissues grow before birth. If both copies of the gene carry a disease-causing variant, a baby can develop Fowler syndrome, a rare inherited condition linked to profound changes in brain and blood vessel formation.
What is a gene?
Within your DNA, a gene is a section that holds information your cells can use to make molecules or regulate processes in the body. Some genes provide the instructions for making proteins, the working parts of cells. Other genes mainly control when certain processes happen, where they happen, and how strongly they run. Together, genes affect how the body develops and functions, and they can shape how you respond to food, stress, or medications. To explore this topic in more detail, you can learn more in the LearnHub.
Overview
FLVCR2Gene function
What if the gene works
The FLVCR2 gene helps cells take up heme, an iron containing molecule used in many proteins. This supports normal cell growth and early development, including in the brain.
Risk
What if the gene does not work
More severe variants in the FLVCR2 gene are linked to Fowler syndrome, which affects blood vessel and brain development before birth. Milder variants may leave some function, which can influence when features appear and how severe they are.
Treatment
What does that mean for your treatment
No FLVCR2-specific treatment or management approach is currently established for pathogenic variants in the FLVCR2 gene.
Conditions associated with FLVCR2
Gene function
What if the gene works
Your cells need a steady supply of heme, an iron-containing molecule used in many everyday processes. The FLVCR2 gene helps control how heme enters cells. Understanding how the FLVCR2 gene works in the body helps explain how cells support energy production and other basic tasks.
The FLVCR2 gene helps move heme from outside the cell to the inside. Its protein sits in the cell membrane and acts as a passage for this important molecule.
By bringing in heme, this gene supports proteins that help cells make energy. It also helps supply heme to other proteins used in routine chemical work across the body.
What is a variant?
A genetic variant is a small difference in the DNA sequence of a gene. These changes are common and are part of normal human diversity, including differences in appearance, metabolism, or the way the body responds to environmental influences. Many variants do not cause any noticeable effect and simply represent natural genetic variation. In some situations, however, 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
Variants in the FLVCR2 gene can change the shape, stability, or cell-surface delivery of its transporter protein, so cells move heme less effectively. In practical terms, this is how FLVCR2 gene variants affect protein function. Some missense variants leave partial activity, while more disruptive splice, nonsense, or frameshift variants can sharply reduce or eliminate the protein. In FLVCR2-related disease, greater loss of function is often linked to earlier and more severe developmental changes before birth.
How variants are linked to conditions
Pathogenic variants in both copies of the FLVCR2 gene cause Fowler syndrome, also called proliferative vasculopathy and hydranencephaly-hydrocephaly syndrome. In practice, FLVCR2 gene variants are linked to a rare condition that affects development before birth, often with major brain changes and fluid buildup in the brain. This association is well established in human genetics and is used to confirm the diagnosis when the right clinical findings and FLVCR2 variants are present.
A variant is not necessarily a diagnosis
Genetic variants are a normal feature of human biology and are common throughout the general population. Most do not have a direct effect on health and instead reflect natural variation among people. For many genes, carrying a variant associated with a condition suggests a possible link rather than a confirmed diagnosis, especially when several genes and environmental factors are involved. In some situations, though, a single well-characterized variant in a particular gene can be enough to confirm a diagnosis.
Are there things that can increase or change my risk?
For FLVCR2, risk is mainly linked to whether a baby inherits harmful changes in both copies of this gene from their parents. There is not yet broadly confirmed evidence that lifestyle, diet, or other outside factors increase or reduce risk related to FLVCR2, so families with concerns about personal risk should speak with a doctor or genetic counselor.
Inheritance of FLVCR2 variants
FLVCR2-related conditions are inherited in an autosomal recessive pattern. In practical terms, how FLVCR2 gene variants are inherited usually means a child must receive one altered copy of the FLVCR2 gene from each parent to be affected. Parents who each carry one variant are typically unaffected carriers, and with each pregnancy there is a 25% chance the child will inherit both altered copies, a 50% chance the child will be a carrier, and a 25% chance the child will inherit neither altered copy. This pattern affects sons and daughters equally.
What does my FLVCR2 result mean for my family?
For families with a disease-causing FLVCR2 result linked to the known FLVCR2-related condition, the pattern is recessive, which means parents are often healthy carriers. Brothers and sisters may also be carriers, and in some families an affected child can occur again. Other relatives may want to learn whether carrier testing is relevant for them, especially when planning a pregnancy.
Genetic information
Genetic testing
How you find out about variants
To look for variants in the FLVCR2 gene, doctors use genetic testing on a blood sample or cheek swab. How genetic testing for FLVCR2 variants works is straightforward: a lab reads the gene’s DNA code and checks for changes that may help explain an inherited condition. Results may show a known variant, no relevant variant, or an unclear finding.
When should I consider getting a genetic test?
Genetic testing for FLVCR2 may be considered when a pregnancy or baby shows severe problems with brain and blood vessel development, especially if there has been a similar pregnancy or affected child in the family. In these families, testing can also show whether both parents carry a changed copy of the gene.
A genetic result is only one part of your health story
Genetic results can provide meaningful insight, but how much they reveal varies by the condition and the specific variant involved. Many factors, including age, environment, lifestyle, and medical history, also shape how the body works over time. For some conditions, especially those influenced by many genes, genetic information provides context rather than certainty and is most useful when considered alongside other parts of care. In other situations, a genetic result may offer a clear answer. In areas like medication response, genetic results can also help place individual experiences in context.
Pharmacogenetics
How variants shape your response to medicine
Genetic variation can affect how people respond to medicines. One person may break down a drug more slowly, while another may process it faster or be more sensitive to its effects. This common difference can influence how well a treatment works and the chance of side effects.
What is Pharmacogenetics?
Pharmacogenetics examines the ways genetic differences can affect a person’s response to medications. It focuses on gene-drug relationships to explain why the same treatment may work differently in different people. With many medicines, genes can influence both how the body handles a drug and how strong its effects are. This information can support treatment choices that are more informed and tailored to the individual. More detail on this subject is available in the LearnHub.
Drugs influenced by the FLVCR2 gene
When should I seek medical advice?
There is not yet a broadly confirmed role for this gene in predicting how medicines will work, so routine medication decisions are not based on it. Questions about side effects, new symptoms, or whether a treatment is right for you are best discussed with your doctor or pharmacist.