The TMEM98 gene helps guide normal eye growth and supports tissues at the back of the eye. This gene plays an important role in helping the eye keep its usual size and shape. If a harmful variant disrupts this job, some people can develop nanophthalmos, where the eyes are smaller than usual, often with strong farsightedness and retinal folds.
What is a gene?
A gene is a stretch of DNA that holds instructions your cells use to make molecules or regulate processes in the body. Some genes contain the directions for building proteins, the parts of cells that carry out much of the work. Other genes mainly control when, where, and how much certain processes take place. Together, genes affect how the body develops and works, and they can influence how you respond to food, stress, or medications. If you want to go into this topic in more detail, you can read more in the LearnHub.
Overview
TMEM98Gene function
What if the gene works
The TMEM98 gene helps guide normal eye development and supports tissues at the back of the eye, especially the retina. It also appears to help control eye size as the eye grows.
Risk
What if the gene does not work
Variants in the TMEM98 gene can disrupt eye growth, causing unusually small eyes with marked farsightedness and sometimes retinal folds or angle closure glaucoma. Milder and more severe variants may influence which eye features show up and how strongly.
Treatment
What does that mean for your treatment
No TMEM98-specific treatment or management approach is currently established. The TMEM98 gene is mainly being studied to better understand eye growth and related eye conditions, rather than to guide a specific medicine choice at this time.
Conditions associated with TMEM98
Gene function
What if the gene works
In the eye, the TMEM98 gene helps cells grow and work in an organized way. Much of the TMEM98 gene function in the eye relates to the retinal pigment epithelium, a thin support layer behind the retina. Research also shows that this gene helps control a protein made from the MYRF gene, which turns sets of genes on at the right time.
Its protein is especially active in the retinal pigment epithelium, which feeds and supports the retina. This activity is linked to normal eye shaping and steady upkeep of nearby tissues.
The protein made from the TMEM98 gene helps regulate a protein made from the MYRF gene, which switches groups of genes on. It keeps that activity more controlled, supporting orderly timing during eye development and tissue maintenance.
What is a variant?
Common genetic variants are small changes in the DNA sequence of a gene. They are a normal part of human diversity and help account for 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, 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 TMEM98 gene can affect protein function by changing the protein’s shape, stability, or ability to interact with partner proteins inside eye cells. Many reported changes are missense variants, meaning they swap one protein building block for another and are thought to alter function rather than completely remove the protein. Milder variants may partly disrupt these interactions, while more severe variants can have a stronger effect and may be linked to earlier or more marked eye findings.
How variants are linked to conditions
Pathogenic variants in the TMEM98 gene are a well-established cause of autosomal dominant nanophthalmos. In TMEM98 gene variants linked to nanophthalmos, people usually have unusually small eyes and marked farsightedness, and some may later develop angle-closure glaucoma. This is a rare inherited eye condition, so a confirmed pathogenic TMEM98 variant can help explain the diagnosis in an affected person or family.
A variant is not necessarily a diagnosis
DNA variants are a normal feature of human biology and are common across the general population. Most do not have a direct effect on health and simply reflect natural human diversity. For many genes, carrying a variant associated with a condition points to a possible link rather than a definite diagnosis, especially when multiple genes and environmental factors 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 factors that increase or reduce health risk related to the TMEM98 gene. Risk usually depends most on the exact gene change and family history, and people with concerns about their personal risk can speak with a doctor or genetic counselor.
Inheritance of TMEM98 variants
TMEM98-related conditions that are clearly established in human genetics are usually inherited in an autosomal dominant pattern. That means a parent carrying a disease-causing variant in the TMEM98 gene can pass it to a child with a 1 in 2, or 50%, chance in each pregnancy. In practical terms, how TMEM98 gene variants are inherited does not depend on whether the child is male or female. A person who does not carry the family variant usually cannot pass it on.
What does my TMEM98 result mean for my family?
Some TMEM98 changes are linked to an inherited eye condition that can run in families in a dominant pattern, which means close relatives such as parents, brothers, sisters, and children may also carry the same change. For many families, this means relatives may want to learn whether the variant is present, especially if there is farsightedness or unusually small eyes in the family. In some families, the change appears for the first time in one person rather than being passed down.
Genetic information
Genetic testing
How you find out about variants
Variants in the TMEM98 gene are found through genetic testing, usually from a blood or saliva sample. A lab reads the gene’s DNA code to look for changes, often as part of TMEM98 gene variant testing within a larger eye disease panel or an exome test. This can help show whether a TMEM98 gene variant may explain an eye condition in you or your family.
When should I consider getting a genetic test?
Consider genetic testing for the TMEM98 gene if you or your child has unusually small eyes, strong farsightedness, or eye pressure problems that suggest an inherited eye condition. Testing can also help when these eye findings run in the family or when doctors are trying to confirm the cause.
A genetic result is only one part of your health story
A genetic result can provide useful 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 works over time. In some conditions, especially those shaped 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 can offer a clear answer. In areas like 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 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 treatment may work well for one person, have less effect in another, or cause more side effects in someone else. These differences are common and are one part of the bigger picture alongside age, health, and other medicines.
What is Pharmacogenetics?
Pharmacogenetics examines how differences in a person’s genes affect the way they respond to medicines. By studying links between genes and medications, it helps explain why the same treatment can work differently in different people. With many drugs, genes influence either how strongly the medicine works or how the body processes it. This information can support treatment decisions that are both better informed and more individualized. More detailed information on this topic is available in the LearnHub.
Drugs influenced by the TMEM98 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 general questions about symptoms, side effects, or treatment are best discussed with your doctor or pharmacist.
History
The TMEM98 gene entered the medical literature during the early 2000s as researchers mapped and named many previously uncharacterized human genes. In recent decades, awareness of this gene’s role has grown mainly through eye genetics research rather than through public attention. A key step came when family studies linked variants in the TMEM98 gene to inherited eye conditions, especially nanophthalmos, a form of unusually small eye size. Building on this early work, scientists connected findings from affected families with broader sequencing studies that helped confirm its clinical relevance. Over time, descriptions became more precise as genetic testing made it easier to recognize the same gene across different families and populations.