The KRT31 gene provides instructions for making a hair keratin, a protein that helps give hair its strength and shape. The protein made by this gene helps your cells build the hair shaft, especially the firm inner part of each strand. If this gene does not work as expected, hair may be more fragile, break more easily, or have a different texture. Differences in the KRT31 gene can help explain some of the natural variation in hair appearance from one person to another.
What is a gene?
Genes are stretches of DNA that carry instructions your cells use to make molecules or direct activities in the body. In some cases, those instructions are used to make proteins, the parts of cells that do much of the work. Other genes mainly regulate when certain processes happen, where they happen, and how strongly they run. Together, genes affect how the body develops and functions, and they can also shape how you respond to food, stress, and medications. For a deeper look at this topic, you can find more in the LearnHub.
Overview
KRT31Gene function
What if the gene works
The KRT31 gene helps make a keratin protein in the hair shaft. This protein supports the hair’s inner structure, helping strands stay strong, flexible, and shaped normally.
Risk
What if the gene does not work
Changes in the KRT31 gene can range from milder to more severe and may reduce how well its protein links with other keratins in cells that make hair. This can weaken the growing hair shaft's inner framework.
Treatment
What does that mean for your treatment
No KRT31-specific treatment or management approach is currently established for people with a pathogenic variant in the KRT31 gene.
Gene function
What if the gene works
In the hair follicle, the KRT31 gene helps build the sturdy fibers that make up the hair shaft. Its protein becomes part of the inner framework of growing hair, where it supports strength, shape, and flexibility. This helps explain what the KRT31 gene does in normal hair growth and hair structure.
The KRT31 gene helps produce one of the keratin proteins used in the hair shaft. Inside growing hair cells, this protein adds firm, springy support to the strand's inner structure.
The protein from the KRT31 gene joins with partner keratin proteins to form strong support fibers inside hair-forming cells. These fibers act like an internal scaffold, helping each hair strand keep its shape as it grows.
As hair matures, the protein made from the KRT31 gene becomes part of a tough protein network. This supports normal resistance to everyday bending, brushing, and friction.
What is a variant?
A genetic variant is a small change in the DNA sequence of a gene. These changes are common and help shape normal human diversity, including differences in appearance, metabolism, or how the body responds to environmental influences. Many variants have no noticeable effect and are simply part of natural genetic variation. Sometimes, 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 KRT31 gene can change the shape, stability, or binding of the K31 keratin protein inside hair forming cells, which helps explain how KRT31 gene variants affect protein assembly. Some changes are mild and slightly weaken the way keratin strands join together. More disruptive variants can shorten the protein or make it break down early, leaving much less usable protein. That range can lead to different levels of disruption in the cell’s internal hair fiber framework.
How variants are linked to conditions
Changes in the KRT31 gene do not yet have a broadly confirmed link to a specific health condition, though research on KRT31 gene variants linked to conditions can evolve over time. Anyone with a confirmed KRT31-related finding should use advice from their doctor or genetic counselor, because interpretation depends on the exact variant and the person's medical history.
A variant is not necessarily a diagnosis
Genetic variants are a common and normal feature of human biology. Most do not directly affect health and simply reflect natural differences among people. For many genes, having a variant associated with a condition points to a possible link rather than a certain diagnosis, particularly when several genes and environmental influences also play a role. In some situations, though, one well understood variant in a particular gene is 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 KRT31 gene. If a change in KRT31 is found, it is usually more helpful to look at the specific gene result and any hair changes or other symptoms than to focus on outside risk factors alone.
Inheritance of KRT31 variants
There is not yet a broadly confirmed, disease-specific inheritance pattern for the KRT31 gene. Current evidence has not established a single Mendelian pattern, so descriptions of KRT31 gene inheritance remain cautious and may change as research develops. The KRT31 gene is located on chromosome 17, which is an autosome, so each person inherits one copy from their mother and one copy from their father. This also means sons and daughters can inherit a KRT31 variant in the same general way.
What does my KRT31 result mean for my family?
There is not yet a broadly confirmed inheritance pattern tied to a specific health condition for KRT31, though this can change as research grows. If you have a specific KRT31 result and want to understand what it could mean for close relatives, a doctor or genetic counselor can help explain it in the context of your family.
Genetic information
Genetic testing
How you find out about variants
To find out whether you carry a variant in the KRT31 gene, a lab can do genetic testing for KRT31 variants using a blood sample, saliva, or a cheek swab. The lab reads the gene’s DNA sequence and compares it with the usual sequence to identify differences, then reports whether a variant was found.
When should I consider getting a genetic test?
There isn't yet a broadly established, KRT31-specific clinical reason for genetic testing. Decisions about testing are best made with a doctor or genetic counselor, based on your symptoms, hair changes, and family history.
A genetic result is only one part of your health story
A genetic result can provide useful insight, but how much it explains varies by the condition and the type of variant. Over time, many factors, including lifestyle, environment, age, and medical history, also shape how the body functions. For some conditions, especially those affected by many genes, genetic information offers context rather than certainty and is most useful when considered 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 into context.
Pharmacogenetics
How variants shape your response to medicine
Genetic variation can affect how people respond to medicines. A treatment that works well for one person may work less well for another, or may cause more side effects, because the body can absorb, break down, or respond to a drug in different ways. These differences are common and can influence how strongly a medicine works or how sensitive someone is to it.
What is Pharmacogenetics?
Pharmacogenetics examines how genetic differences can shape the way a person responds to medications. By studying connections between genes and drugs, it helps explain why the same treatment may work differently from one person to another. For many medicines, genes affect how strongly a drug works or how the body handles it. This information can support treatment decisions that are more informed and more individualized. More detail on this topic is available in the LearnHub.
Drugs influenced by the KRT31 gene
When should I seek medical advice?
There is not yet a broadly confirmed role for this gene in guiding medication choice or response, so questions about side effects, new symptoms, or how a medicine may affect you are best discussed with your doctor.