Is Eczema Genetic? What Your 23andMe Polygenic Risk Score Really Means

Is Eczema Genetic? What Your 23andMe Polygenic Risk Score Really Means

This article is for educational purposes only. It is not a substitute for advice from a licensed physician, board-certified medical geneticist, or board-certified genetic counselor. For any decisions about testing, treatment, or care, consult a qualified clinician. In emergencies, call 911.

Bottom line: A 2023 multi-ancestry gene study found 91 risk regions linked to atopic dermatitis, often just called eczema. It showed that immune-system genes, not the well-known skin-barrier gene FLG, drive most of eczema’s total heritability. A 23andMe “higher likelihood” polygenic score reflects a shift in the odds for a group of people. It is not a personal guarantee. Only a dermatologist’s exam can diagnose eczema. Two new FDA-approved biologic drugs now target the immune pathways this research points to.

What you’ll learn

• Why eczema risk comes from many genes working together, not one dominant mutation.
• How to turn a “higher likelihood” polygenic score into a clear picture of personal odds.
• The real difference between a direct-to-consumer (DTC) risk report — the kind sold by services like 23andMe — and a dermatologist’s diagnosis.
• What the two newest FDA-approved eczema biologics involve, and what GINA does and does not protect.

1. Is Eczema Genetic? Why One Gene Isn’t the Whole Story

Atopic dermatitis is almost always just called eczema. It does not pass down through one gene the way some family conditions do. It does not skip generations in a set pattern. It does not affect a fixed share of children either. Instead, eczema risk builds up slowly from many common gene changes spread across a person’s DNA. Each change adds only a small nudge on its own.

The strongest single risk factor found so far is a gene called filaggrin, known as FLG. FLG sits on chromosome 1, in a cluster of genes that manage the skin’s outer barrier. FLG normally helps build the layer of skin that keeps water in and allergens out. When FLG stops working right, that barrier gets weak. Eczema and other allergic reactions then become more likely.

Government geneticists call FLG changes a risk factor, not a sure cause. These changes are common in the general public. Most people who carry one do not develop severe eczema. A “positive” family history tied to FLG is a nudge, not a fixed sentence.

A 2023 study pooled genetic data from more than one million people across several ancestries. It compared 65,107 people with eczema to 1,021,287 people without it. This is the largest eczema gene study to date. Researchers found 91 gene regions, called loci, linked to eczema risk.

The surprising part was not about the skin-barrier gene. It was that immune-system genes add more to total eczema risk than skin-barrier genes alone. Researchers measure this kind of contribution using heritability — how much of the difference in eczema risk between people traces back to genes, not a prediction for any one person. These immune genes control how the body fights germs and reacts to allergens. Many of them cluster around a signaling pathway built on a protein called IL-13, which helps drive allergic swelling. This immune-first pattern helps explain why the newest eczema drugs target immune signals. They do not target the skin barrier directly.

Study / source	Sample	Key finding
2023 multi-ancestry gene study	65,107 cases / 1,021,287 controls	91 risk regions; immune genes outweigh skin-barrier genes in heritability
MPAACH cohort, 2024	438 children, 69% African ancestry	FLG carriers: ~2.00x odds of moderate/severe disease, ~2.81x odds of food allergy
Lebrikizumab (Ebglyss)	ADvocate1 & ADvocate2 phase 3 trials	FDA approved 2024-09-13, targets IL-13
Nemolizumab (Nemluvio)	ARCADIA 1 & 2 phase 3 trials, n=1,728	FDA approved 2024-12-13, targets the IL-31 itch pathway

This pattern looks nothing like a single-gene condition. BRCA1 and BRCA2 raise breast and ovarian cancer risk from one gene each. Cystic fibrosis works the same way, tied to one gene called CFTR. Each of those genes has a large, fairly steady effect. Eczema has no single gene like that. Dozens of common gene changes each nudge risk slightly, and the skin-barrier gene simply nudges hardest among them.

A skin doctor or allergist is the right specialist to check active skin symptoms. A board-certified genetic counselor can help translate a complex gene result. This shows what it means for one family. Picture eczema risk like a group photo made of many faint brushstrokes rather than one bold signature. No single stroke decides the whole picture.

Section recap: Eczema risk comes from many common gene changes acting together. The skin-barrier gene FLG is the strongest single factor. But immune-signaling genes matter more for overall risk.

2. Your Real Odds: Turning a Risk Score Into Plain Numbers

The MPAACH study followed 438 children, most of African ancestry. It looked closely at eczema genes in daily life. About 14 out of every 100 children in the study, 13.7%, carried an FLG change. This change turns off the gene’s normal skin-barrier job. Researchers call this a loss-of-function variant.

Children carrying this change had roughly double the odds of moderate-to-severe eczema instead of mild eczema. This was compared with children who did not carry the change. They also had roughly triple the odds, 2.81 times, of having a food allergy.

An odds ratio of 2.00 does not mean 200 out of 100 children get severe eczema. It compares two groups’ chances against each other, not against some fixed target. Imagine 100 children with eczema who look alike in every way except this one gene change. Imagine children without the change split close to evenly between mild and moderate-to-severe disease. Children with the change would tilt more toward the moderate-to-severe side. The shift is real, but most FLG carriers still do not end up with the most severe form.

A 23andMe polygenic eczema report works on a different scale. It combines more than 2,100 common gene changes into one score, then ranks a person’s result against other people. The report’s own notes say its accuracy shifts across ancestry groups. These groups include European, Hispanic/Latino, East and Southeast Asian, South Asian, Sub-Saharan African, and Northern African or Western Asian. A “higher likelihood” flag describes a shift in the odds for a group of people who share gene traits. It does not describe a fixed outcome for one person.

Think of a polygenic score like a stew made from thousands of small ingredients, each adding a little flavor. No single ingredient decides the final taste. A DTC report only tastes the finished stew. It estimates how that stew compares with other stews on average. It cannot tell you exactly which ingredient mattered most for you.

A primary care doctor or board-certified genetic counselor can help explain what a DTC result means. They can do this with a person’s or family’s history of eczema.

Section recap: An odds ratio like 2.00 shifts the balance of chances for a group. It does not predict one child’s outcome. A 23andMe score works the same way, and its accuracy varies by ancestry.

3. Genetic Test vs. Diagnosis: What a 23andMe Report Can (and Can’t) Tell You

Doctors do not diagnose eczema with a gene test. A skin doctor or allergist diagnoses it by asking about symptoms and checking the skin. They look for chronic itching and dry patches. They also check for a rash in the creases of the elbows and knees. No blood draw or DNA sample is part of a standard eczema check.

This differs from cancer genetics. There, a test such as BRCA1/BRCA2 sequencing can guide a treatment decision. There is no insurance-covered single-gene test for eczema that works the same way. A 23andMe polygenic report is not a stand-in for either kind of clinical test.

Research studies like MPAACH use detailed FLG sequencing to study skin-barrier genes in depth. That level of testing is a research tool. It is not something available to consumers through a standard DNA report today. A 23andMe eczema report instead estimates a broad trend. It is built from thousands of common gene changes, not a close look at any single gene.

	DTC polygenic report (e.g., 23andMe)	Clinical diagnosis
What it measures	A broad trend from thousands of common gene changes	Actual skin symptoms, from history and exam
Confirms eczema?	No	Yes
Who orders it	Anyone, no prescription needed	A dermatologist or allergist
Covered by insurance?	Often paid out of pocket	Often covered as a medical visit
Best next step	Share the result with a doctor for context	Confirms or rules out active eczema and guides treatment

A genetic counselor can help interpret a DTC eczema result. This works along with personal and family history. The National Society of Genetic Counselors keeps a searchable directory at NSGC.org.

Section recap: A 23andMe polygenic score is a broad estimate, not a test that confirms disease. Only a skin doctor’s exam, sometimes with an allergist’s input, can confirm active eczema.

4. Reading Your Result: Risk Score, Diagnosis, and Uncertainty

Three different things get confused constantly, and separating them matters:

• A polygenic risk score — a broad estimate from a service like 23andMe, not based on current symptoms.
• A confirmed clinical diagnosis — made by a skin doctor or allergist after an exam and symptom history.
• Ordinary dry skin or a mild rash — common conditions that can look like eczema but are not the same disease.

Unlike a single-gene test, a polygenic score carries no “variant of uncertain significance,” a label often shortened to VUS. A VUS is a single gene change whose effect on disease risk is not yet clear. Score uncertainty comes from a different source. The score was built mostly from studies of certain ancestry groups. So it transfers less well to other groups. It also cannot fully account for a person’s surroundings.

A higher-likelihood result does not mean eczema is present today. A lower-likelihood result also does not guarantee it will never appear. Ongoing itching, a rash in the skin creases, or persistent dry skin are real reasons to see a doctor. Genes should stay background context, not the main reason to seek or avoid care.

Think of the score like a weather forecast. It calls for a raised chance of rain sometime next month. That forecast is useful context for planning ahead. It cannot tell you whether to carry an umbrella today. Only today’s actual skin, not a distant forecast, answers that question.

Bringing a DTC report to a skin doctor visit tends to produce clearer next steps. This works better than researching it alone late at night. A primary care doctor can also help. They can decide whether a referral to a specialist makes sense.

Section recap: A polygenic score, a confirmed diagnosis, and ordinary dry skin are three different things. Active symptoms, not a genetic score, are the real reason to see a doctor.

5. Can Eczema Be Prevented in a Baby With a Family History?

There is no way yet to change a person’s genetic tendency toward eczema. Prevention here means lowering risk and catching early signs. It does not mean getting rid of eczema completely.

Daily moisturizer use, sometimes called emollient therapy, is often recommended for infants at higher genetic risk. Keeping the skin barrier hydrated may reduce water loss through the skin. It may also lower the chance of flares. Avoiding known triggers, such as harsh soaps or scratchy fabrics, is standard advice alongside moisturizing. Moisturizing is a reasonable, low-risk habit to start early, though it cannot guarantee eczema will never appear.

Researchers describe a pattern called the atopic march. Early skin-barrier problems in infancy sometimes come before other symptoms. These include food allergy, asthma, and hay fever later in childhood. The MPAACH study’s link between the skin-barrier gene and food allergy fits this pattern well. Most children with eczema do not travel the full march through every stage.

Watch for these early signs, especially with a family history of eczema, food allergy, asthma, or hay fever:

• Dry, itchy patches that do not improve with regular moisturizer
• A rash in the creases of the elbows, knees, wrists, or ankles
• Skin that reddens or thickens from constant scratching
• Sleep disruption from itching in an infant or toddler

A pediatrician or skin doctor can help decide whether extra allergy testing makes sense for a child with these signs. The same goes for follow-up care. This especially applies with a strong family history.

Section recap: Moisturizing and avoiding triggers lower risk and support early detection. Full prevention is not guaranteed. Watching for the atopic march matters more than trying to prevent eczema outright.

6. The Newest Eczema Drugs: Two FDA Approvals Built on the Immune-Gene Discovery

Standard eczema care starts with moisturizers and avoiding triggers. Topical steroid creams are medicines that calm inflammation on the skin. They are usually the next step for flares. For moderate-to-severe cases that do not respond well to creams, treatment moves to systemic drugs. These are medicines that act throughout the body, not just on the skin.

Lebrikizumab, sold as Ebglyss, is a biologic — a lab-made antibody drug. It blocks IL-13, the same immune-signaling protein the 2023 gene study flagged as key to eczema’s immune-driven side. The FDA approved it on September 13, 2024. It is approved for patients age 12 and older weighing at least 40 kilograms with moderate-to-severe eczema. Two phase 3 trials, ADvocate1 and ADvocate2, showed real gains in skin-severity scores versus placebo at 16 weeks.

Nemolizumab, sold as Nemluvio, targets a different immune signal: the IL-31 receptor. This receptor helps drive the itch sensation in eczema. It is the first FDA-approved antibody drug built just for this itch pathway. The FDA approved it on December 13, 2024, for patients 12 and older, used together with topical steroid or calcineurin-inhibitor creams. Two phase 3 trials, ARCADIA 1 and ARCADIA 2, covered 1,728 people combined. They showed a big drop in itch and skin severity compared with placebo.

Drug	Target	FDA approval	Trial evidence
Lebrikizumab (Ebglyss)	IL-13, an immune-signaling protein	2024-09-13, ages 12+ / ≥40kg	ADvocate1 & ADvocate2 phase 3 trials
Nemolizumab (Nemluvio)	IL-31 receptor, an itch-signaling target	2024-12-13, ages 12+, with topical treatment	ARCADIA 1 & 2 phase 3 trials, n=1,728

Both drugs target immune signals rather than the skin barrier. That approach lines up with the 2023 gene study’s finding. Immune genes, more than the skin-barrier gene, drive total eczema risk. Health Canada’s approval status for both drugs was not independently confirmed at the time of writing. Readers should check current Health Canada records before assuming Canadian availability matches the US timeline.

A separate review of systemic eczema drugs comes from the Cochrane-affiliated GREAT trial database. It stresses that treatment choice should weigh real trial evidence, not marketing claims alone. Neither lebrikizumab nor nemolizumab cures eczema or reverses the genetic tendency behind it. Both target disease activity once it is already present.

Whether either drug fits a particular case is a personal question. It needs a talk with a skin doctor or allergist. That specialist should know the patient’s full history and insurance coverage.

Section recap: Lebrikizumab (2024-09-13) and nemolizumab (2024-12-13) are the newest FDA-approved eczema biologics. Both target immune signals from the 2023 gene study, not the skin barrier itself.

7. What This Means for Your Kids and Grandkids

Eczema is polygenic rather than tied to one specific gene. Because of this, cascade testing does not apply the way it does for a single-gene condition. Cascade testing means offering the same genetic test to relatives. It happens once one family member tests positive for a specific gene change. There is no single eczema gene to test relatives for in that way.

Parents with eczema, or a positive DTC polygenic result, do not have a fixed inheritance number to hand down. What they can do is watch infants for early signs. These include dry skin, a mild rash in the skin creases, or persistent itching. Telling a child’s doctor about these signs early leads to faster, more useful follow-up.

The atopic march describes a rough sequence some children follow:

1. Early skin-barrier problems and eczema in infancy
2. Food allergy appearing in the first few years
3. Asthma developing in early-to-mid childhood
4. Allergic rhinitis, chronic hay-fever-like nasal symptoms, appearing later

Most children with eczema do not move through every step. The MPAACH cohort found a link between the skin-barrier gene and food allergy. This shows why pediatricians pay attention to this pattern in genetically at-risk families.

Most children of a parent with eczema will not develop severe disease themselves. Family risk awareness is useful. It is not the same as a guaranteed outcome.

A child’s doctor or allergist can help a family decide whether early allergy testing makes sense. This applies once a child shows persistent symptoms.

Section recap: Cascade testing does not apply to a polygenic condition like eczema. Family risk means watching for early signs. It means discussing the atopic march with a child’s doctor, not testing relatives for one gene.

8. Insurance, Employment, and Telling Your Family

The US Genetic Information Nondiscrimination Act, known as GINA, became federal law in 2008. It stops health insurers from using a genetic test result, including a 23andMe polygenic score. They cannot use it to deny coverage or set premiums. It also stops employers from using genetic information in hiring, firing, or promotion decisions.

Covered by GINA	Not covered by GINA
Health insurance eligibility and premiums	Life insurance
Employer hiring, firing, and promotion decisions	Disability insurance
—	Long-term-care insurance

That gap matters before applying for one of the uncovered policy types. A family member might already have a diagnosed skin condition, not just a genetic risk flag. Other US laws may offer separate protection once a condition is actually diagnosed, apart from GINA’s genetic-information rules. A benefits advisor or genetic counselor can help confirm what protection applies in a specific case.

Canadian readers have a parallel law: the Genetic Non-Discrimination Act, in force since 2017. It says no one can be forced to take a genetic test or share results. This applies to getting goods, services, or insurance in many cases. How it is enforced depends on provincial insurance rules. Protection can vary by province as a result.

Whether to tell siblings or children about a DTC eczema result deserves thought. It should not be a rushed announcement. Some people share results right away, hoping it prompts earlier attention to a child’s symptoms. Others wait until symptoms or a real diagnosis appear. Neither approach is wrong.

A genetic counselor can help a family think through timing and wording. This especially helps when a teenager or young adult relative is involved.

Section recap: GINA blocks genetic discrimination in US health insurance and employment but not life, disability, or long-term-care insurance. Canada’s GNDA offers a parallel protection with provincial variation.

Frequently Asked Questions

Will I get eczema if my 23andMe result shows a higher likelihood? No, not automatically. A higher-likelihood result shifts the odds for a group of people with a similar genetic profile. Most people with that profile never develop moderate-to-severe eczema. Only a skin doctor’s exam can confirm active disease.

Will my children inherit eczema from me? Eczema does not follow a single-gene inheritance pattern. So there is no fixed percentage to hand down. Children of a parent with eczema carry a somewhat higher chance. Most of them will not develop severe disease.

Will this affect my health or life insurance? GINA stops US health insurers and employers from using a genetic test result against someone. It does not cover life, disability, or long-term-care insurance. Those policy types remain a real gap to understand before testing or sharing results.

Can my employer find out about my genetic test result? Under GINA, US employers cannot legally use genetic information in hiring, firing, or promotion decisions.

Should I get a second opinion on my result? Yes, whenever symptoms or family history raise real questions. A board-certified genetic counselor can add clarity. So can a second skin doctor, since eczema severity and triggers vary widely from person to person.

Summary

Eczema is a polygenic condition, not a single-gene disorder. A 2023 gene study found 91 risk regions. It showed that immune-signaling genes drive more of the total risk than the well-known skin-barrier gene FLG. A 23andMe “higher likelihood” result reflects that shared genetic picture. It is not a diagnosis, and it cannot replace a dermatologist’s exam.

Treatment has kept pace with the genetics. Lebrikizumab’s FDA approval in September 2024 and nemolizumab’s approval in December 2024 both target immune signals. Neither targets the skin barrier directly. That matches the immune-first picture the 2023 study showed. GINA protects against genetic discrimination in US health insurance and employment. Real gaps remain for life, disability, and long-term-care coverage.

Anyone with a family history of eczema, or a new DTC risk flag, should raise these questions with a doctor. Persistent itching and a rash in the skin creases deserve the same talk. So does dry skin that does not respond to regular moisturizer.

A useful starting point: write down the result, any symptoms noticed, and relevant family history before an appointment. Bring that summary to a skin doctor, allergist, or genetic counselor. A focused talk, grounded in real evidence, tends to give the clearest next steps. This works far better than searching alone online.

This article is for educational purposes only. It is not a substitute for advice from a licensed physician, board-certified medical geneticist, or board-certified genetic counselor. For any decisions about testing, treatment, or care, consult a qualified clinician. In emergencies, call 911.

References

1. Budu-Aggrey A, et al. European and multi-ancestry genome-wide association meta-analysis of atopic dermatitis highlights importance of systemic immune regulation. Nature Communications, 2023-10-04;14:6172. PMID 37794016. DOI 10.1038/s41467-023-41180-2. https://pubmed.ncbi.nlm.nih.gov/37794016/
2. Virolainen SJ, et al. Filaggrin loss-of-function variants are associated with atopic dermatitis phenotypes in a diverse, early-life prospective cohort. JCI Insight, 2024-04-02;9(9):e178258. PMID 38564302. DOI 10.1172/jci.insight.178258. https://pubmed.ncbi.nlm.nih.gov/38564302/
3. US FDA / Eli Lilly. FDA approval of lebrikizumab-lbkz (Ebglyss) for moderate-to-severe atopic dermatitis, 2024-09-13. https://www.fda.gov/drugs
4. US FDA / Galderma. FDA approval of nemolizumab-ilto (Nemluvio) for moderate-to-severe atopic dermatitis, 2024-12-13. https://www.fda.gov/drugs
5. Simpson EL, et al. Efficacy and safety of lebrikizumab in moderate-to-severe atopic dermatitis: ADvocate1 and ADvocate2 randomized clinical trials. JAMA Dermatology, 2023. https://pubmed.ncbi.nlm.nih.gov/
6. Silverberg JI, et al. Phase 3 randomized trials of nemolizumab in moderate-to-severe atopic dermatitis: ARCADIA 1 and ARCADIA 2. 2024. https://pubmed.ncbi.nlm.nih.gov/
7. Irvine AD, McLean WHI, Leung DYM. Filaggrin mutations associated with skin and allergic diseases. New England Journal of Medicine, 2011;365:1315-1327. https://www.nejm.org/doi/full/10.1056/NEJMra1011040
8. National Institutes of Health, MedlinePlus Genetics. FLG gene: filaggrin. https://medlineplus.gov/genetics/gene/flg/
9. National Human Genome Research Institute (NHGRI). Genetic Information Nondiscrimination Act (GINA): overview and protections. https://www.genome.gov/about-genomics/policy-issues/Genetic-Discrimination
10. Davis DMR, et al., American Academy of Dermatology (AAD) Work Group. Guidelines of care for the management of atopic dermatitis in adults. Journal of the American Academy of Dermatology, 2023-2024. https://www.aad.org/member/clinical-quality/guidelines/atopic-dermatitis
11. Joint Task Force on Practice Parameters, American Academy of Allergy, Asthma & Immunology (AAAAI). Atopic dermatitis: practice parameter update, atopic march position, 2023. https://www.aaaai.org/practice-resources/statements-and-practice-parameters
12. Drucker AM, et al. Systemic immunomodulatory treatments for atopic dermatitis: a systematic review and network meta-analysis. JAMA Dermatology / GREAT database, 2020. https://jamanetwork.com/journals/jamadermatology
13. Government of Canada, Department of Justice. Genetic Non-Discrimination Act (GNDA), S.C. 2017, c. 3. https://laws-lois.justice.gc.ca/eng/acts/g-2.5/
14. 23andMe Health Predisposition Reports. Eczema (Atopic Dermatitis) Genetic Health Report: methodology overview. https://23andme.org/clinicians/genetic-reports/health-predispositions/

Last updated: 2026-09-20

Author: genelumen editorial team. This article aggregates 14 sources from peer-reviewed research and public health agencies (tier 1=10, tier 2=3, tier 3=1), including NIH, NHGRI, FDA, AAD, and AAAAI.

This article is for educational purposes only and is not a substitute for medical advice from a licensed physician, board-certified medical geneticist, or board-certified genetic counselor. In emergencies, call 911 (US/Canada) or 119 (Japan).

🇯🇵 For readers in Japan — a separate Japanese edition written for Japan’s healthcare system (not a translation): https://genelumen.com/ja/ja-genetic-diseases/atopic-dermatitis-genetic-risk-gwas-flg