The ENG gene helps build and maintain healthy blood vessels, especially the inner lining that keeps vessel walls stable and blood flow well controlled. If you carry a harmful variant in the ENG gene, some blood vessels may form in an unusual way, which can lead to frequent nosebleeds, small visible red spots on the skin or mouth, or larger abnormal artery to vein connections in organs such as the lungs, liver, or brain. Pathogenic variants in the ENG gene are a known cause of hereditary hemorrhagic telangiectasia, an inherited condition that affects blood vessels.
What is a gene?
Genes are stretches of DNA that give your cells instructions for making molecules or directing activities in the body. Some genes provide the code for proteins, which do much of the cell’s work. Others mainly regulate when certain processes happen, where they happen, and how active they are. As a group, genes affect how the body grows and works, and they can influence how you react to food, stress, and medicines. For a deeper look at this subject, visit the LearnHub.
Overview
ENGGene function
What if the gene works
The ENG gene helps cells lining blood vessels grow and respond to signals. This supports normal blood vessel formation and repair.
Risk
What if the gene does not work
Variants in the ENG gene most often cause hereditary hemorrhagic telangiectasia, with repeated nosebleeds and abnormal blood vessel connections in the lungs or brain. Milder and more severe variants can affect when signs start and how extensive they are.
Treatment
What does that mean for your treatment
No ENG-specific treatment or drug choice is currently established in clinical guidelines. Care is guided by the person’s HHT features, although people with pathogenic variants in the ENG gene often receive especially careful monitoring for lung and brain blood vessel changes; the endoglin pathway is also being studied as a treatment target.
Conditions associated with ENG
Gene function
What if the gene works
ENG is especially active in the cells that line blood vessels. It helps these cells read growth signals, build new vessels, and keep vessel walls organized. Understanding how the ENG gene supports blood vessel growth helps explain its role in everyday circulation and healing.
The ENG gene helps blood vessel cells respond to growth signals and other chemical messages. This helps guide when those cells grow, move, or settle into place.
During growth and healing, the ENG gene supports angiogenesis (the making of new blood vessels). It helps vessel lining cells multiply and arrange themselves into new paths for blood flow.
This gene helps the inner lining of a blood vessel stay coordinated with the rest of the vessel wall. That support helps blood vessels keep a steady, organized structure.
The ENG gene helps vessel lining cells adjust to the steady force of moving blood. This supports normal remodeling, meaning small shape and size changes that keep circulation working smoothly.
What is a variant?
A genetic variant is a small change in the DNA sequence within a gene. These changes are common and are part of normal human diversity, including differences in appearance, metabolism, or how the body responds to environmental influences. Many variants do not cause any noticeable effect and simply represent natural genetic variation. In some situations, though, a variant can more substantially change how a gene functions and may contribute to or cause a genetic condition.
Genetic variants
What if the gene does not work
Variants in the ENG gene often reduce the amount of endoglin protein on the cell surface or change its shape, which weakens signaling that helps blood vessel cells organize and mature. This is how ENG gene variants affect blood vessel signaling in hereditary hemorrhagic telangiectasia. Some variants leave partial activity, while more disruptive variants can cause little or no protein. That can shift how strongly vessel formation is affected and, in some people, how early features appear.
How variants are linked to conditions
Pathogenic variants in the ENG gene cause hereditary hemorrhagic telangiectasia type 1, often called ENG-related HHT. This inherited condition commonly involves repeated nosebleeds, small visible blood vessels on the lips, tongue, face, or hands, and abnormal blood vessel connections in the lungs or brain. Ongoing bleeding can also lead to iron deficiency anemia, and finding a pathogenic ENG variant confirms the diagnosis.
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 instead represent natural human diversity. For many genes, carrying a variant associated with a condition indicates a possible link rather than a definite diagnosis, especially when multiple genes and environmental factors are involved. In some situations, however, a single well-characterized variant in a specific gene may be enough on its own to confirm a diagnosis.
Are there things that can increase or change my risk?
Having a harmful change in the ENG gene is the main factor, because it strongly raises the chance of hereditary hemorrhagic telangiectasia. Problems can be more likely or more noticeable with pregnancy, blood thinners, or poorly controlled high blood pressure in some people. Regular checkups can help find blood vessel changes in the lungs, brain, or liver early.
Inheritance of ENG variants
ENG gene inheritance for hereditary hemorrhagic telangiectasia usually follows an autosomal dominant pattern. If you carry a disease-causing variant in the ENG gene, each child has a 50% chance of inheriting that same variant. Men and women are affected and can pass it on equally, because the ENG gene is on chromosome 9, not a sex chromosome. Some people have a new, de novo variant that was not inherited from either parent.
What does my ENG result mean for my family?
Changes in the ENG gene are usually passed down in families in a dominant pattern, so close relatives such as parents, brothers, sisters, and children may also carry the same change. In practice, this means each child of someone with an ENG change has a 1 in 2 chance of having it too. Family members who carry the change may have nosebleeds, small widened blood vessels, or hidden blood vessel problems in organs, while others may have milder signs.
Genetic information
Genetic testing
How you find out about variants
To find out about variants in the ENG gene, genetic testing uses a blood or saliva sample so a lab can read the gene’s spelling and check for missing or extra pieces. This is how ENG genetic testing works: it can detect many variants, although some results do not predict exactly which symptoms a person will have.
When should I consider getting a genetic test?
Consider testing for the ENG gene if you or close relatives have hereditary hemorrhagic telangiectasia, a condition that can cause frequent nosebleeds, small red spots on the skin or mouth, or unusual blood vessels in the lungs, brain, or liver. Testing can help confirm the cause and identify family members who may also need checks.
A genetic result is only one part of your health story
How informative a genetic result is depends on both the condition and the type of variant involved, even though the result itself can offer meaningful insight. Over time, the way the body works is shaped by many influences, including lifestyle, environment, age, and medical history. With some conditions, particularly those influenced by many genes, genetic information provides context instead of certainty and is most useful when considered together with other parts of care. In other cases, the result may supply a clear answer. In areas such as medication response, genetic findings can help place individual experiences in perspective.
Pharmacogenetics
How variants shape your response to medicine
Genetic variation can affect how people respond to medicines. Small inherited differences can change how the body absorbs, breaks down, transports, or responds to a drug. This helps explain why the same treatment works well for one person, works less well for another, or causes more side effects in someone else. These differences are common and are one reason medication response can vary from person to person.
What is Pharmacogenetics?
Pharmacogenetics examines the ways genetic differences affect a person’s response to medicines. By studying links between genes and medications, it helps explain why the same treatment can work differently in different people. For many drugs, genes influence both how the body handles a medicine and how strong its effects are. This information can support more informed, more personalized treatment decisions. More detail on this topic is available in the LearnHub.
Drugs influenced by the ENG gene
When should I seek medical advice?
There is not yet a broadly confirmed role for this gene in guiding how medicines are chosen or dosed, so if you have concerns about side effects, drug interactions, or how a treatment is working, talk with your doctor.
History
Throughout history, people have described recurrent nosebleeds and visible blood vessel changes running in families, a pattern now recognized in some people with variants in the ENG gene. In the 1990s, researchers mapped one form of hereditary hemorrhagic telangiectasia, historically called Osler-Weber-Rendu syndrome, to chromosome 9 and then identified the ENG gene as the cause in many affected families. This was an important step because it showed that the condition had distinct genetic subtypes rather than a single cause. From these first observations, research expanded steadily. Studies of the ENG gene then helped connect inherited bleeding symptoms with the biology of blood vessel development, shaping modern diagnosis and family testing.