The IGF2 gene helps control growth before birth and supports how cells use nutrients to build and repair tissues. This gene plays an important role in growth signals that tell the body when to grow. If its activity is too low or too high, a baby may grow less or more than expected, and some people have growth conditions such as Silver-Russell syndrome or Beckwith-Wiedemann syndrome. Changes affecting the IGF2 gene can also play a part in some cancers.
What is a gene?
Genes are stretches of DNA that hold instructions your cells use to make molecules or direct processes throughout the body. Some genes provide the code for proteins, which are the parts of cells that do much of the work. Others are used mainly to regulate when specific processes happen, where they take place, and how active they are. Taken together, genes affect how the body grows and works, and they can influence how you respond to food, stress, and medications. More detail on this topic is available in the LearnHub.
Overview
IGF2Gene function
What if the gene works
The IGF2 gene helps make a growth signal that is especially important before birth. It supports fetal and placental growth and also helps guide cell growth in some tissues after birth.
Risk
What if the gene does not work
Changes affecting the IGF2 gene or its imprinting can alter growth before birth. Reduced activity is linked to growth restriction, while increased activity can cause overgrowth; mild to severe variants may change when features appear and how marked they are.
Treatment
What does that mean for your treatment
No established treatment or management approach is currently directed by a pathogenic or loss-of-function variant in the IGF2 gene. IGF2 is being studied as a biomarker and possible drug target in some cancers and growth conditions, but this has not led to routine gene-directed treatment.
Conditions associated with IGF2
Gene function
What if the gene works
Before birth, your body uses the IGF2 gene to guide steady growth across many tissues. It helps developing cells receive clear signals to grow, divide, and use nutrients well. This is a key part of what the IGF2 gene does in growth before birth and early development.
The IGF2 gene helps make a protein signal that tells developing cells when to grow. This signal is especially important before birth, when body size and organ formation are being set.
After IGF2 is released, it attaches to receiver proteins on cells and passes growth messages inward. This helps tissues coordinate growth in a controlled way.
IGF2 supports cells as they divide and make new tissue during development. This helps muscles, organs, and other body structures build normal size and shape.
IGF2 activity is usually controlled mainly by the copy inherited from the father. This parent-specific pattern, called imprinting (using mainly one parent's copy), helps keep growth signals in the right range.
What is a variant?
A genetic variant is a small change in the DNA sequence within a gene. These changes are common and help make up normal human diversity, including differences in appearance, metabolism, or how the body responds to environmental influences. Many variants have no noticeable effect and simply represent natural genetic variation. In some situations, however, 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 IGF2 gene often change how much IGF2 is made rather than altering the protein itself, because this gene is tightly controlled by imprinting (parent-of-origin switching of gene activity). Some changes in the IGF2 gene can lower or raise IGF2 production only slightly, while more severe variants can markedly disrupt the protein or shut down expression from the active copy. In IGF2-related growth conditions, larger functional changes often go with earlier or more noticeable features.
How variants are linked to conditions
Among the conditions linked to the IGF2 gene, Silver-Russell syndrome is the best established. Pathogenic variants can cause poor growth before and after birth, feeding difficulties, and a head that looks relatively large for the body. Because only the copy inherited from the father is active, this diagnosis is usually associated with a paternal IGF2 variant. Rare other IGF2 changes have also been associated with overgrowth.
A variant is not necessarily a diagnosis
Genetic variants are a routine part of human biology and are widespread in the general population. Most do not have a direct effect on health and simply reflect normal human variation. For many genes, carrying a variant associated with a condition suggests a possible link rather than a definite diagnosis, especially when several genes and environmental factors play a role. In some situations, though, a single well understood variant in a particular gene can be enough to confirm a diagnosis.
Are there things that can increase or change my risk?
There isn't yet broadly confirmed evidence on specific factors that increase or reduce health risk related to the IGF2 gene itself. In some families, risk can depend on the exact change in the gene and whether it was inherited from the mother or father, so personal guidance from a doctor or genetic counselor can be helpful.
Inheritance of IGF2 variants
How IGF2 variants are inherited is a little unusual because this gene is imprinted, which means the copy from one parent is mostly active while the other is mostly switched off. For known IGF2-related conditions, inheritance is best described as autosomal dominant with a parent-of-origin effect: the variant usually matters when it is on the copy inherited from the father. A father carrying a disease-causing IGF2 variant can pass it to each child with a 50% chance. A mother may also pass on the variant, but her copy often has little or no effect because it is usually not the active copy.
What does my IGF2 result mean for my family?
There isn't yet a broadly confirmed, simple family inheritance pattern tied to IGF2 that applies across all IGF2-related findings. This is because IGF2 can be affected by genomic imprinting, a process where the effect depends on which parent the change came from. If you have a specific IGF2 result and questions about what it could mean for relatives, a doctor or genetic counselor can explain it in the context of your family.
Genetic information
Genetic testing
How you find out about variants
Genetic testing for IGF2 variants uses a blood or saliva sample to read the IGF2 gene and look for DNA changes linked to inherited conditions. Depending on the test, the lab may check the gene’s spelling, look for missing or extra pieces, and report whether a variant was found, not found, or remains uncertain.
When should I consider getting a genetic test?
Genetic testing may be worth considering if a child has unusual growth patterns that started before birth, such as being much smaller than expected or, less often, unusually large, especially with body asymmetry or a family history of a growth condition. Changes involving the IGF2 gene can help explain some rare growth conditions and may clarify whether they run in families.
A genetic result is only one part of your health story
A genetic result can be informative, but how much it reveals depends on the condition and the kind of variant involved. Many other factors, including lifestyle, environment, age, and medical history, also shape how the body functions over time. For some conditions, especially those influenced by many genes, genetic information provides context rather than certainty and is best understood together with 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 put personal experiences into context.
Pharmacogenetics
How variants shape your response to medicine
Genetic variation can affect how your body responds to medicines. Small differences in genes can change how a drug is absorbed, broken down, moved through the body, or how strongly it acts at its target. This is common and helps explain why the same medication may work well for one person but less well for another. It can also influence how sensitive someone is to side effects.
What is Pharmacogenetics?
Pharmacogenetics examines how genetic differences can affect a person’s response to medications. It studies the relationships between genes and drugs to help explain why the same treatment may work differently from one person to another. For many medicines, genes can influence how strongly a drug works or how the body processes it. This understanding can support treatment decisions that are more informed and more individualized. To explore this topic further, you can learn more in the LearnHub.
Drugs influenced by the IGF2 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 used, so questions about treatment, side effects, or new symptoms are best discussed with your doctor.
History
Across cultures and time periods, inherited patterns were noted long before scientists could explain them. Interest in the IGF2 gene grew as researchers studied growth-related signals in the late 20th century and began linking this gene to fetal development and certain overgrowth conditions. A major turning point came when the IGF2 gene helped reveal genomic imprinting, a process in which a gene’s effect depends on whether it is inherited from the mother or the father. This was an important shift in genetics because it showed that inheritance is not always as simple as getting one working copy from each parent. From these first observations, research expanded steadily, and the IGF2 gene became part of the story of Beckwith-Wiedemann syndrome and later some cancer studies. These historical steps shaped today’s understanding.