The protein made by the MME gene helps your body break down small signaling proteins, which supports healthy nerve, kidney, and blood vessel function. If this gene does not work properly, those proteins can build up, and some people develop an inherited nerve condition that causes numbness, foot weakness, cramps, or balance problems over time. In medicine, the MME gene is also well known because it makes neprilysin, a protein involved in heart failure treatment and in the brain’s normal protein clearance.
What is a gene?
Genes are stretches of DNA that carry instructions your cells use to make molecules or manage processes throughout the body. Certain genes provide the directions for producing proteins, which are the parts of cells that do much of the work. Others are involved mainly in regulating when specific processes happen, where they happen, and how active they are. As a group, genes affect how the body develops and functions, and they can influence your response to food, stress, and medications. For a deeper look at this topic, visit the LearnHub.
Overview
MMEGene function
What if the gene works
The MME gene makes an enzyme that breaks down small protein signals in the body. This helps control salt and fluid balance, blood pressure, nerve signaling, and how tissues respond to stress.
Risk
What if the gene does not work
Variants in the MME gene are best known for causing a late-onset inherited nerve condition with numbness, pain, or weakness in the feet and legs. Milder or severe variants can affect symptom timing and how much balance or walking changes.
Treatment
What does that mean for your treatment
No MME-specific treatment or management approach is currently established for people with pathogenic variants in the MME gene. The MME gene is still clinically relevant in drug research because its protein, neprilysin, is the target of sacubitril in some heart failure treatments, but that use is not guided by inherited MME variants.
Conditions associated with MME
Gene function
What if the gene works
Many everyday body signals need to be switched off at the right time. The MME gene helps make a protein on the cell surface that cuts up certain small signaling proteins after they have done their job. This keeps communication between cells more balanced in tissues such as the kidneys, blood vessels, lungs, and brain.
The protein from the MME gene acts like tiny scissors for short protein messengers called peptides. It cuts them into smaller pieces so their signal fades once it is no longer needed.
By clearing used peptide signals, this protein helps keep cell communication from lasting too long. That steady cleanup is part of how the MME gene works in the body from day to day.
Some of the peptides it breaks down help control blood vessel tension and how the kidneys handle salt and water. This supports normal blood pressure and fluid balance.
In the nervous system, this protein also helps end the action of certain peptide signals linked to pain and other nerve communication. This allows messages to rise and settle in a more controlled way.
What is a variant?
A genetic variant is a minor difference in the DNA sequence within a gene. These changes are common and help account for normal human diversity, such as differences in appearance, metabolism, or how the body responds to environmental influences. Many variants do not have any noticeable effect and are simply part of natural genetic variation. In some situations, however, a variant changes how a gene functions more substantially and may contribute to or directly cause a genetic condition.
Genetic variants
What if the gene does not work
Variants in the MME gene can leave the neprilysin protein reduced, misshapen, unstable, or poorly placed on the cell surface, which lowers enzyme activity. This is how MME gene variants affect protein function, and the changes can range from milder variants to more disruptive ones with little or no working protein. In people with disease-causing variants in both copies, that difference may influence how early neuropathy appears and how marked it becomes.
How variants are linked to conditions
Pathogenic variants in both copies of the MME gene cause Charcot-Marie-Tooth disease type 2T, an inherited peripheral nerve condition. This MME gene and Charcot-Marie-Tooth disease link is the main well-established association in human genetics. People with this diagnosis often develop slowly progressive foot weakness, numbness, and balance problems in adulthood.
A variant is not necessarily a diagnosis
Genetic variants are common across the general population and are a usual feature of human biology. Most do not directly affect health and simply reflect natural differences among people. For many genes, carrying 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?
There is not yet broadly confirmed evidence on specific everyday factors that clearly increase or reduce health risk related to the MME gene. Risk can depend mainly on the exact gene change and family history, so people with concerns about personal risk may benefit from talking with a doctor or genetic counselor.
Inheritance of MME variants
For families asking how MME gene variants are inherited, the best established pattern is autosomal recessive. This means a person usually develops an MME-related inherited neuropathy only when they receive one disease-causing variant from each parent. Parents who each carry one variant are often unaffected, and with each pregnancy there is a 25% chance their child will inherit both variants, a 50% chance the child will be a carrier, and a 25% chance the child will inherit neither variant.
What does my MME result mean for my family?
For MME, the best-established family pattern is a recessive nerve condition, which means close relatives may also carry the gene change even if they do not have symptoms. Brothers and sisters may have the same condition or be carriers, and parents are often carriers. Children of someone with an MME-related condition will usually be carriers, and their own chance of being affected depends on the other biological parent's results.
Genetic information
Genetic testing
How you find out about variants
To find out whether you carry a variant in the MME gene, doctors use MME genetic testing on a blood or saliva sample. A lab reads the gene’s DNA code and compares it with the usual sequence to look for variants, helping clarify whether a known disease-causing variant is present.
When should I consider getting a genetic test?
Consider testing for MME if you or close relatives have unexplained nerve problems in the feet and legs, such as numbness, burning pain, foot drop, or slowly worsening weakness, especially when symptoms run in the family. An MME change can help confirm an inherited nerve condition and may clarify family risk.
A genetic result is only one part of your health story
A genetic finding can offer useful insight, although how much it can tell you varies by the condition and the type of variant involved. How the body functions over time is also shaped by many factors, including lifestyle, environment, age, and medical history. For some conditions, especially those influenced by many genes, genetic information provides context rather than certainty and is most helpful when viewed alongside other parts of care. In other situations, a genetic result may give a clear answer. In areas such as medication response, genetic results can also help put individual experiences into perspective.
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 breaks down a drug, moves it through the body, or responds to it at its target. This helps explain why the same medication may work well for one person, seem less helpful for another, or cause more side effects in someone else. These differences are common and are one part of why treatment response varies from person to person.
What is Pharmacogenetics?
Pharmacogenetics examines how differences in genes affect the way people respond to medicines. It studies gene-drug patterns to understand why the same treatment can work differently in different people. For many drugs, genes influence how strong a medicine’s effects are or how the body handles it. This information can support more informed, individualized treatment choices. More detailed information on this topic is available in the LearnHub.
Drugs influenced by the MME 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 general medication questions, side effects, or concerns about treatment are best discussed with your doctor. MME is being studied because it makes neprilysin, a protein affected by some heart failure medicines, but this research is not currently used to guide routine prescribing.
History
First described in the scientific literature as part of early genetics, the MME gene became known through the protein marker CD10, which doctors used to help classify certain leukemia and lymphoma cells. In the 1980s, researchers linked this marker to an enzyme already studied in kidney tissue, bringing separate lines of research together. Over time, scientists’ understanding of the gene’s function has changed as MME was recognized in many tissues, not only in blood cancers. Interest later widened when neprilysin, the protein made from the MME gene, became important in heart failure drug development and in research on brain diseases such as Alzheimer’s. These historical steps shaped today’s understanding of MME as a gene with roles well beyond its original clinical use.