The LRP2 gene gives your body instructions for a receptor that helps certain cells, especially in the kidneys and during early development, take in and recycle important proteins, vitamins, and chemical signals. If this gene does not work properly, the kidneys may leak proteins into the urine, and the development of the brain, eyes, ears, and other organs can be affected. Pathogenic variants in both copies of the LRP2 gene are linked to Donnai-Barrow syndrome, a rare inherited condition. LRP2 is mainly known in medicine rather than popular culture.
What is a gene?
Genes are stretches of DNA that carry instructions your cells use to make molecules or regulate processes in the body. Some genes hold the information needed to produce proteins, the parts of cells that do much of the work. Other genes mainly guide when certain processes happen, where they happen, and how strongly they occur. Together, genes affect how the body develops and works, and they can also influence how you respond to food, stress, or medications. To explore this topic further, you can read more in the LearnHub.
Overview
LRP2Gene function
What if the gene works
The LRP2 gene helps cells take in and recycle proteins, vitamins, and hormones. It is especially active in the kidneys, where it helps keep useful substances from being lost in urine.
Risk
What if the gene does not work
More disruptive variants in the LRP2 gene can cause Donnai-Barrow syndrome, which may affect brain development, hearing, vision, and kidney function; milder variants can lead to a broader range of features and differences in when symptoms appear.
Treatment
What does that mean for your treatment
No LRP2-specific treatment or management approach is currently established. A pathogenic variant in the LRP2 gene does not currently direct any guideline-based drug choice, so care is tailored to the person's symptoms and organ involvement.
Conditions associated with LRP2
Gene function
What if the gene works
Your kidneys and several other lining tissues use the LRP2 gene to pull helpful molecules back into cells instead of letting them wash away. This supports everyday balance in the body. The protein made from this gene acts as a surface pickup system for many different substances.
One major part of what the LRP2 gene does in the kidneys is reclaim small proteins, vitamins, and hormone carriers from the forming urine. This helps your body keep useful substances instead of losing them in waste.
The protein from the LRP2 gene sits on the cell surface and grabs many kinds of cargo. The cell then pulls that cargo inside, a process called endocytosis (cell uptake), so it can be reused or processed.
The protein made from the LRP2 gene helps cells take back carriers for vitamin D and vitamin A after these pass through the kidney filter. This supports steady vitamin handling and helps conserve nutrients your body uses every day.
Early in development, the protein from the LRP2 gene helps cells manage signaling molecules that guide how tissues take shape. These signals support orderly growth in organs such as the brain, eyes, and kidneys.
What is a variant?
A genetic variant is a small alteration in the DNA sequence of a gene. These changes are common and help account for normal human diversity, including differences in appearance, metabolism, or the way the body responds to environmental influences. Many variants do not lead to any noticeable effect and simply represent natural genetic variation. In some situations, however, a variant can change how a gene functions more significantly and may contribute to or cause a genetic condition.
Genetic variants
What if the gene does not work
Variants in the LRP2 gene can change the protein’s shape, stability, or delivery to the cell surface, which helps explain how LRP2 gene variants affect protein function. Some variants partly reduce its ability to bind and bring substances into the cell, while more severe variants can leave little or no working protein. This loss of function ranges from milder to more marked, and with two nonworking copies it is linked to Donnai-Barrow syndrome, with severity sometimes tracking with how much protein activity remains.
How variants are linked to conditions
Pathogenic variants in the LRP2 gene cause Donnai-Barrow syndrome, a rare inherited condition also called facio-oculo-acoustico-renal syndrome. People with this diagnosis may have differences affecting hearing, vision, brain development, the diaphragm, and kidneys, although features vary from person to person. When two pathogenic variants are found in the LRP2 gene, they can confirm the diagnosis in the right clinical setting.
A variant is not necessarily a diagnosis
Genetic variants are a usual part of human biology and are widespread in the general population. Most do not directly affect health and instead reflect normal human diversity. For many genes, having a variant associated with a condition suggests a possible link rather than a certain diagnosis, especially when several genes and environmental factors also play a role. In some situations, though, a single well-characterized variant in a specific gene is enough to confirm a diagnosis.
Are there things that can increase or change my risk?
For LRP2-related conditions, risk is mostly determined by inheritance: it usually happens when a child receives two changed copies of the LRP2 gene, one from each parent. There is not broadly confirmed evidence that lifestyle or environmental factors meaningfully change this risk.
Inheritance of LRP2 variants
Variants in the LRP2 gene linked to Donnai-Barrow syndrome are inherited in an autosomal recessive pattern. This means a child usually inherits one altered copy of the LRP2 gene from each parent, while the parents are often healthy carriers. When both parents carry an LRP2 gene variant, each pregnancy has a 25% chance of being affected, a 50% chance of producing a carrier child, and a 25% chance of producing a child without the familial variants. In practical terms, how variants of the LRP2 gene are inherited depends on both parents passing on the altered gene copy.
What does my LRP2 result mean for my family?
For the main recognized condition linked to the LRP2 gene, the family pattern is recessive. This usually means parents are healthy carriers, and brothers or sisters may also be affected or may be carriers. Other close relatives, such as siblings of the parents, can sometimes be carriers too, so a family result may matter beyond one person.
Genetic information
Genetic testing
How you find out about variants
In practice, how genetic testing for LRP2 variants works is straightforward: a lab reads DNA from a blood or saliva sample and checks the LRP2 gene for variants. Results may show a variant linked to an LRP2-related condition, a harmless change, or a finding that is still unclear.
When should I consider getting a genetic test?
Genetic testing for the LRP2 gene may be considered when a baby or child has signs of Donnai-Barrow syndrome, such as hearing loss, major vision problems, developmental delay, or birth differences affecting the diaphragm, brain, or kidneys. It can also be useful when this condition runs in the family or both parents are known carriers.
A genetic result is only one part of your health story
A genetic result can give valuable insight, but how much it reveals depends on the condition and the kind of variant involved. Many factors, including lifestyle, environment, age, and medical history, influence how the body functions over time. For some conditions, especially those shaped by many genes, genetic information provides context rather than certainty and is most useful when viewed 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 put individual experiences in context.
Pharmacogenetics
How variants shape your response to medicine
Genetic variation can affect how people respond to medicines. Small differences in DNA can change how the body absorbs, breaks down, transports, or responds to a drug, so the same treatment may work better for one person than for another. This is common and can influence how much benefit someone gets from a medicine or how sensitive they are to side effects.
What is Pharmacogenetics?
Pharmacogenetics examines how differences in genes affect the way people respond to medicines. It looks at links between genes and drugs to help explain why the same treatment may work differently from one person to another. With many medications, genes can influence both how strongly a drug works and how the body handles it. This information can support more informed, individualized treatment decisions. More on this topic is available in the LearnHub.
Drugs influenced by the LRP2 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 adjusted. If you have side effects, questions about a medicine, or concerns about your health, it is best to talk with your doctor or pharmacist.
History
The LRP2 gene entered medical research through studies of a large receptor protein first identified in the kidney and later named megalin. In the 1990s, scientists connected that protein to the LRP2 gene and recognized it as part of the low density lipoprotein receptor family. From these first observations, research expanded steadily. Work in animal models then showed that changes in this gene could affect early development and organ formation. In the 2000s, pathogenic variants in the LRP2 gene were linked to Donnai-Barrow syndrome, giving clinicians a clear genetic explanation for a rare inherited condition. Since then, the history of the LRP2 gene has grown through studies in kidney, eye, ear, and developmental medicine.