The MERTK gene helps certain cells clear away worn out material, especially in the retina, the light sensing tissue at the back of the eye. This gene plays an important role in keeping retinal cells working day after day. If the MERTK gene does not work properly, waste can build up and damage vision. In people with two disease causing variants, this can lead to an inherited retinal condition, often with night blindness and vision loss that gradually gets worse.
What is a gene?
Genes are stretches of DNA that give your cells instructions for making molecules or managing processes in the body. Some genes carry the information needed to make proteins, which are the working parts of cells. Other genes mainly regulate when certain processes happen, where they take place, and how active they are. Taken together, genes affect how the body develops and works, and they can also shape how you respond to food, stress, or medications. For a more detailed look at this topic, you can learn more in the LearnHub.
Overview
MERTKGene function
What if the gene works
The MERTK gene helps certain cells clear away worn-out cell material, especially in the retina and immune system. This supports healthy vision and balanced inflammation.
Risk
What if the gene does not work
Variants in the MERTK gene most often cause an inherited retinal condition, usually retinitis pigmentosa. People may develop worsening night blindness and narrowing side vision, and more severe variants can bring earlier onset and faster vision loss.
Treatment
What does that mean for your treatment
For pathogenic variants in the MERTK gene, no MERTK specific treatment or management approach is currently established in clinical guidelines. The MERTK gene is under study as a target for gene therapy in inherited retinal disease and in some cancer drug research, but these approaches remain investigational.
Conditions associated with MERTK
Gene function
What if the gene works
Every day, your body needs a steady cleanup system to remove worn out cell material and keep tissues calm. The MERTK gene helps clear cell debris and supports the retina’s light sensing cells. Its protein sits on the cell surface and passes along signals that tell certain cells when to take in and remove material.
The MERTK gene helps certain cells recognize, engulf, and remove worn out cells and leftover cell fragments. This keeps tissues tidy and supports normal cell turnover without spilling cell contents into nearby tissue.
In the retina, the MERTK gene helps support cells clear used pieces shed by light sensing cells each day. This routine cleanup helps the retina stay organized so vision can work smoothly in daily life.
Signals from the MERTK gene help immune cells that clean up debris switch from removal to recovery mode after debris is taken in. This supports a more controlled immune response and helps tissues settle back into normal balance.
What is a variant?
A genetic variant is a small change in the DNA sequence within a gene. These changes are common and help create normal human diversity, such as differences in appearance, metabolism, or how the body reacts to environmental influences. Many variants do not have any noticeable effect and simply represent natural genetic variation. In some cases, though, 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 MERTK gene can reduce or shut down the receptor by changing its shape, blocking its movement to the cell surface, or causing early breakdown. Some also disrupt splicing, leaving the protein shortened or missing. Milder changes may leave some activity, while more severe variants can cause near-complete loss of function, which helps explain how MERTK gene variants affect retinal cells and why vision loss may start earlier in some people.
How variants are linked to conditions
Pathogenic variants in the MERTK gene are a well-established cause of inherited retinal disease, especially MERTK gene retinitis pigmentosa and some forms of severe early-onset retinal dystrophy. People with two disease-causing variants, usually one inherited from each parent, can develop progressive vision loss that often begins with night blindness and narrowing side vision. In this setting, finding pathogenic MERTK variants can confirm the genetic diagnosis.
A variant is not necessarily a diagnosis
Genetic variants are common across the general population and are a normal feature of human biology. Most do not directly affect health and simply contribute to natural differences among people. For many genes, a variant associated with a condition points to a possible link rather than a certain diagnosis, particularly when several genes and environmental influences play a role. In contrast, a single well-characterized variant in a particular gene can sometimes confirm a diagnosis.
Are there things that can increase or change my risk?
For MERTK-related inherited retinal disease, risk is mainly shaped by whether someone has disease-causing changes in both copies of the MERTK gene, often inherited from each parent. There is not yet broadly confirmed evidence that lifestyle or environmental factors meaningfully change this risk.
Inheritance of MERTK variants
MERTK-related disease is inherited in an autosomal recessive pattern. In practical terms, how MERTK variants are inherited usually means a person has received one altered copy of the MERTK gene from each parent. Parents who each carry one variant are often unaffected themselves, and with each pregnancy they have a 25% chance of having a child with the condition, a 50% chance of having a child who is a carrier, and a 25% chance of having a child with no familial variant. Sons and daughters are affected at similar rates.
What does my MERTK result mean for my family?
For families with a disease-causing change in the MERTK gene, close relatives may also carry the same change, even if they do not have vision problems. Brothers and sisters could be affected or be carriers, and parents are usually carriers. Other relatives may also want to learn whether they carry the family’s MERTK change, especially if they are planning children.
Genetic information
Genetic testing
How you find out about variants
Genetic testing for MERTK variants usually uses a blood or saliva sample. A lab reads the DNA in the MERTK gene, often as part of an inherited retinal disease panel, to look for variants that may explain certain patterns of vision loss and help clarify whether the finding fits an inherited eye condition.
When should I consider getting a genetic test?
Genetic testing for the MERTK gene may be worth considering if you or a family member has an inherited eye condition such as retinitis pigmentosa, especially with night blindness and gradually narrowing side vision. It can help confirm the cause and clarify whether the condition runs in the family.
A genetic result is only one part of your health story
A genetic result can provide useful information, but what it can tell you varies based on the condition and the kind of variant involved. Over time, lifestyle, environment, age, and medical history all play a role in how the body functions. In some conditions, especially those shaped by many genes, genetic information gives context rather than certainty and is most helpful when considered with the rest of a person’s care. In other situations, a genetic result may offer a clear answer. In areas such as medication response, genetic results can also help put individual experiences into context.
Pharmacogenetics
How variants shape your response to medicine
Genetic variation can affect how people respond to medicines. Small differences in genes can change how the body breaks down a drug, moves it through the bloodstream, or responds to it at its target. This is common and can help explain why the same treatment works well for one person, has less effect in another, or causes more side effects in someone else.
What is Pharmacogenetics?
Pharmacogenetics looks at how genetic differences can shape a person’s response to medications. It studies links between genes and drugs to help explain why the same treatment may work differently from one person to another. For many medicines, genes can affect how the body processes a drug and how strongly that drug works. This understanding can help support more informed and more individualized treatment decisions. You can learn more about this topic in LearnHub.
Drugs influenced by the MERTK gene
When should I seek medical advice?
There is not yet a broadly confirmed role for this gene in guiding medication choice or response. If you have questions about side effects, a new prescription, or how your medicines fit with your overall health, talk with your doctor or pharmacist.
History
MERTK entered genetics through cancer research, when scientists traced it to the viral oncogene v-mer found in birds and then identified the related human gene. It was later grouped with AXL and TYRO3 as part of the TAM receptor family, which helped organize research on this branch of cell signaling. From these first observations, research expanded steadily. In the early 2000s, MERTK gained clinical attention when pathogenic variants were linked to inherited retinal dystrophy, including some forms of retinitis pigmentosa. That finding connected earlier laboratory work with a clear human condition and made MERTK an established gene in eye genetics. Since then, its history has grown through studies in both rare inherited disease and cancer biology.