Is Severe Acne Genetic? What Twin and Gene Studies Mean for Parents

Is Severe Acne Genetic? What Twin and Gene Studies Mean for Parents

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: Research shows that severe acne runs strongly in families. A large UK twin study found that about 4 out of 5 parts of the differences in acne between women traced back to genes. But no single gene causes it. The best DNA score so far explains fewer than 6 out of 100 parts of acne risk. So a DNA report cannot tell a parent whether their child will get severe acne. What matters more is getting treatment that follows the 2024 dermatology guidelines. Those guidelines recommend isotretinoin for acne that is leaving scars.

What you’ll learn

• What twin studies and large gene studies actually show about acne and genes
• Why “highly inherited” does not mean “easy to predict from DNA”
• What a consumer “Severe Acne” DNA report can and cannot tell you
• Which treatments are approved in the US and Canada, what iPLEDGE is, and how genetic privacy laws work

How severe acne is inherited: many genes, not one

Acne starts inside the hair follicle. A follicle is the tiny tube a hair grows from. Each follicle has an oil gland attached to it. Doctors call this pair the pilosebaceous unit, which simply means “hair follicle plus oil gland.” The gland makes sebum, which is the skin’s natural oil.

Here is what goes wrong, according to the US National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS):

• Skin cells lining the follicle stick together instead of shedding.
• They mix with sebum and plug the pore.
• Skin bacteria grow inside the plugged follicle.
• The body reacts with inflammation, which means swelling, redness, heat and pain.

Severe acne is a polygenic condition. Polygenic means many genes each add a tiny push. It is not like a single-gene disease, where one changed gene passed from a parent is enough. Think of it like height. No single “tall gene” exists. Hundreds of small effects add up.

The twin evidence

Twin studies compare identical twins, who share all their genes, with non-identical twins, who share about half. In 2002, researchers studied about 3,100 adult women in the TwinsUK registry. They estimated that acne has a heritability of 81%. Heritability is a population number. It tells you how much of the differences between people in a group traces back to genes.

It does not mean that 81 out of 100 people get acne from their genes. It means that, of the differences in acne between these women, roughly 4 out of 5 parts traced back to genetic differences. The study had limits. It included only women, it relied on self-reported acne, and it was done in the UK.

The large gene studies

A genome-wide association study, or GWAS, scans the DNA of thousands of people. In plain terms, it is a large gene study that compares people with and without a condition. Each spot in the DNA linked to the condition is called a locus (plural: loci).

Study	People studied	Main finding
Navarini et al., 2014	1,893 severe acne cases vs 5,132 controls, plus a replication group	3 loci near the genes OVOL1, FST and TGFB2, all in one signalling pathway (TGF-beta)
Petridis et al., 2018	3,823 severe acne cases vs 16,144 controls; 26,722 people total in the combined analysis	15 risk loci; many affect how hair follicles form and are maintained
Mitchell et al., 2022	20,165 people with acne from nine European-ancestry groups	29 new loci, for 46 known acne risk loci in total
Brinks et al., 2026	Review of gene studies across hair-follicle diseases	Shared biology across diseases of the follicle

The 2014 study also found something useful. Two of those genes, OVOL1 and TGFB2, were less active in skin with acne than in normal skin. The 2018 study pointed to genes that shape the follicle itself. Together, these results suggest that inherited differences in skin and follicle structure matter.

A 2026 review from NYU places acne among a wider group of hair-follicle diseases. These diseases share common biology. The review notes that large gene studies are increasingly used to improve drug development.

Each single variant has only a tiny effect. One consumer report, sold by 23andMe, combines more than 8,500 variants into one estimate. That is how polygenic scores work. They add up thousands of tiny pushes.

If acne runs in your family, a primary care doctor or dermatologist can use that history. A DNA test is not needed for that.

Section recap: Severe acne is shaped by many genes, each with a tiny effect. Twin studies show strong inheritance, and large gene studies have now found 46 linked spots in the DNA.

How big is the risk? Family history versus a DNA score

Acne itself is very common. In the TwinsUK study, about 14 out of every 100 adult women reported a history of acne. In a large French survey of adults, about 46 out of 100 said they had acne at some point. Numbers vary a lot by group and by how acne is defined. Severe, deep, scarring acne is much less common than ordinary breakouts.

Heritability is not personal risk

Heritability describes a group. It does not give one person’s chance. A trait can be highly heritable and still be hard to predict for any one child. That is exactly the case with acne.

The 2022 gene study built a polygenic risk score from its results. A polygenic risk score is a single number that adds up many small DNA effects. From here on, this article calls it a “risk score.” In a separate group of people, that score explained up to 5.6% of the differences in acne risk.

Here is what that means in everyday terms:

• Picture all the reasons people differ in acne risk as 100 pieces.
• The best DNA score explains fewer than 6 of those 100 pieces.
• The other 94 or more pieces are not captured by the score.

So why the gap between 81% and 5.6%? Twin studies capture all inherited effects at once, including ones nobody has found yet. A risk score only counts the variants scientists have already found. Many inherited effects are still unknown.

Family history is a cruder but practical signal

Factor	What studies found	What it means in plain words
A parent had acne	Pooled odds ratio 2.91	Roughly 3 times the odds of acne, at the group level
Overweight or obese BMI	Pooled odds ratio 2.36	Roughly 2.4 times the odds of acne in these studies
Male vs female sex	Pooled odds ratio 1.07, not clearly different	No clear difference overall
One risk variant from the 2014 study	Odds ratio 1.17 to 1.20	A small nudge, not a cause

An odds ratio compares the odds of a condition in two groups. Odds are not the same as risk. The family-history finding does not mean a child is 3 times as likely to get severe acne. It is a group-level link from many studies.

No published study in this evidence base gives an absolute lifetime risk of severe acne for a child of an affected parent. No study here gives one for a high risk score either. Any website that quotes such a number for an individual should be read with care.

There is one more limit. The 2022 study included only people of European ancestry. The score may work less well for people of other ancestries.

A pediatrician or dermatologist can weigh family history alongside what they see on the skin. That is still the most useful way to judge a child’s situation.

Section recap: Acne is strongly inherited across groups, but DNA scores explain fewer than 6 out of 100 parts of the differences between people. Family history is a practical signal to share with a clinician, not a precise forecast.

Testing options: what a consumer “Severe Acne” report can and cannot do

Direct-to-consumer (DTC) tests are DNA kits sold straight to the public. 23andMe has offered a “Severe Acne” report as part of its 23andMe+ Premium membership. According to the company, the report uses a statistical model built with machine learning. The model looks at more than 8,500 genetic variants, plus a person’s ethnicity and sex.

This is a company description of its own product. It is not independent proof of accuracy. No published accuracy figures for this report are part of this article’s evidence base.

How a DTC report compares with medical care

Question	DTC polygenic report	Clinical care for acne
What it does	Estimates a statistical likelihood	A clinician examines the skin and recommends treatment
Is there a diagnostic gene test?	No	No gene test diagnoses common acne
Does it change treatment?	Not on its own	Treatment depends on acne type and severity
Who orders it?	The consumer	A clinician, based on symptoms

There is no insurance-covered genetic test that diagnoses common acne. Acne is assessed in the clinic. A doctor or dermatologist looks at the skin and chooses a treatment plan.

Genetic or hormone testing can matter in a small number of cases. Sometimes acne is one sign of a rare syndrome or a hormone disorder. In those cases, a dermatologist or an endocrinologist (a hormone specialist) decides which tests to order. They base that choice on symptoms, not on a home kit.

Some websites offer to “interpret” raw DNA files from consumer tests. These tools are not clinically validated. Their results should not guide health decisions.

If a DNA report raised questions, a board-certified genetic counselor can help explain it. A directory is available at the National Society of Genetic Counselors (NSGC.org).

Section recap: A consumer “Severe Acne” report gives a statistical estimate, not a diagnosis. Acne is diagnosed by a clinician looking at the skin, and that is what guides treatment.

Reading the result: “increased likelihood” is not a diagnosis

Genetic test results usually fall into one of three types. Only one of them applies to a consumer acne report.

• Diagnostic result: confirms a condition. None exists for common acne.
• Risk estimate: a shift in likelihood based on many small DNA effects. This is what a polygenic acne report gives.
• VUS (variant of uncertain significance): a single gene change whose meaning is not yet known. This idea comes from single-gene testing. It does not apply to risk scores.

An “increased likelihood” result does not mean that a person, or their child, will get severe acne. A “typical likelihood” result does not mean they won’t. Recall that the best known score explains fewer than 6 out of 100 parts of acne risk.

Think of a weather forecast that says “slightly higher chance of rain.” You might pack an umbrella. But you would still look out the window before deciding what to wear.

Factors a DNA report does not capture

NIAMS lists several non-genetic factors that affect acne:

• Hormones: Androgens are hormones that rise during puberty. They enlarge the oil glands. Pregnancy can also affect acne.
• Medicines: Hormone-containing medicines, corticosteroids and lithium can trigger acne.
• Age: Acne is most common in teens and young adults.

Body weight may matter too. Studies link overweight or obese BMI with higher odds of acne. None of this is written into a DNA score.

What drives treatment is what the skin looks like and how acne has behaved over time. A dermatologist can explain how a result fits with a person’s actual skin history.

Section recap: An “increased likelihood” result is a modest statistical shift, not a diagnosis. Hormones, medicines, age and the skin itself still decide care.

Prevention means getting guideline-based treatment

No one can change the genes they inherited. No medicine or procedure is known to prevent the tendency toward acne. In acne, “prevention” means something practical. It means getting the right treatment for the type and severity of acne.

Scarring is the main long-term harm of severe acne. The 2024 American Academy of Dermatology (AAD) guideline recommends isotretinoin for acne that is causing scarring. That is one reason why early action matters.

What the 2024 AAD guideline recommends

The guideline was built on a systematic review of the research. It makes 18 recommendations and 5 good practice statements.

Strength of recommendation	Treatments
Strong	Benzoyl peroxide, topical retinoids (vitamin A creams), topical antibiotics, oral doxycycline
Strong, for specific cases	Oral isotretinoin for acne that is severe, causing psychosocial burden or scarring, or not responding to standard treatment
Conditional (depends on the patient)	Topical clascoterone, salicylic acid, azelaic acid; oral minocycline, sarecycline, combined oral contraceptive pills, spironolactone

The guideline also lists good practice points:

• Combine topical treatments that work in different ways.
• Limit how long oral antibiotics are used.
• Pair oral antibiotics with a topical treatment.
• For larger lesions, consider steroid injections into the spot.

An erratum (a published correction) to the guideline appeared in 2026.

What about diet?

Diet is a common question. The evidence is mixed. A French survey of more than 24,000 adults found a modest link between current acne and eating fatty and sugary foods. People who ate more of these foods had about 1.5 times the odds of current acne. That survey looked at adults, not teens, and it cannot prove cause. A large review found that results on diet were inconsistent across studies.

So a possible modest link exists, but it is not proven. Diet changes are not a substitute for treatment.

A family history of scarring acne is a good reason to book a visit early. A primary care doctor, pediatrician or dermatologist can start the right step of treatment.

Section recap: Prevention in acne means early, guideline-based treatment to limit severity and scarring. Diet links are possible but unproven.

Treatment landscape in the US and Canada

Several newer acne medicines have reached the market in recent years. The table below shows US Food and Drug Administration (FDA) approval dates. It also shows whether Health Canada’s Drug Product Database lists each product as marketed.

An important note: the Canadian dates are the dates marketing began. They are not Health Canada approval dates.

Medicine	What it is	FDA original approval	Canada (Drug Product Database)
CABTREO gel	Clindamycin 1.2% + adapalene 0.15% + benzoyl peroxide 3.1%	2023-10-20 (ages 12 and older)	Marketed since 2024-10-07
WINLEVI cream	Clascoterone 1%, a topical androgen receptor inhibitor	2020-08-26 (ages 12 and older)	Marketed since 2023-09-08
AKLIEF cream	Trifarotene, a topical retinoid	2019-10-04	Marketed since 2019-11-28
SEYSARA tablets	Sarecycline, an oral antibiotic	2018-10-01	No Drug Product Database record found
Isotretinoin capsules	Oral vitamin A derivative	1982-05-07 (Accutane)	Marketed brands include EPURIS, CLARUS and ABSORICA LD

An androgen receptor inhibitor blocks the effect of androgen hormones on the skin. CABTREO combines three active ingredients in one gel. The original Accutane brand is now listed as discontinued, but generic isotretinoin remains available.

Isotretinoin and iPLEDGE

Isotretinoin is an oral medicine for the hardest cases. The US label says it is for severe recalcitrant nodular acne. “Recalcitrant” means acne that has not responded to other treatment. Nodules are inflamed lumps 5 mm or larger. The drug is reserved for people who did not respond to standard treatment, including oral antibiotics.

The label carries a boxed warning, the FDA’s strongest warning. Isotretinoin must not be used by anyone who is or may become pregnant. Even a brief exposure carries an extremely high risk of severe birth defects.

For that reason, the FDA allows isotretinoin to be sold only through a restricted program. This kind of program is called a REMS, which stands for Risk Evaluation and Mitigation Strategy. The US program is called iPLEDGE. Here is how it works:

• Prescribers, pharmacies and patients must all be enrolled.
• Each month, the prescriber confirms that counseling took place.
• Patients who can become pregnant must report two forms of birth control and their pregnancy test results.
• Patients answer educational questions before every prescription.

In Canada, isotretinoin product information also includes strict pregnancy-prevention requirements. A prescriber or pharmacist can explain the steps that apply.

Coverage and cost

Newer brand-name products may need prior authorization from a US insurer. Prior authorization means the insurer must agree before it pays. In Canada, coverage differs between provincial drug plans and private plans. A pharmacist can check what a specific plan covers.

A dermatologist can explain which option fits a teen’s age, skin and health. That conversation matters more than any single new product.

Section recap: The US has approved several newer acne medicines since 2018, and three are marketed in Canada. Isotretinoin works well for severe acne but is tightly controlled because of birth defect risk.

Family implications and talking with a teen

For single-gene diseases, doctors often suggest cascade testing. Cascade testing means offering a genetic test to relatives once one family member tests positive. That approach does not apply to acne. Testing relatives for an acne risk score is not useful, because the score predicts poorly.

What is useful is family history. NIAMS notes that a person may be more likely to get acne if their parents had acne. Pooled studies support this at the group level.

Family history worth sharing with a clinician

• A parent or sibling who had severe, deep or cystic acne
• Acne that left scars in the family
• Any family member who needed isotretinoin
• Acne that started early or lasted into adulthood

Acne often starts in the preteen years. The AAD guideline covers patients as young as 9 years old.

When to bring a teen in

• Deep, painful lumps or cysts appear.
• Spots leave dark marks or pitted scars.
• Over-the-counter products have not helped after a fair trial.
• Acne is affecting mood, sleep, school or social life.

Acne and mood

A 2020 review combined 42 studies. It found that people with acne had higher rates of depression and anxiety. The link was real but modest. Most people with acne are not depressed or anxious. The study also cannot show which comes first. The authors advised doctors to treat acne actively and to consider mental health screening.

The 2022 gene study found some shared genetic roots between acne and hormone levels, hormone-sensitive cancers and psychiatric traits. This is a research-level finding. It does not predict anything about one person.

A teen may feel embarrassed to talk about their skin. Calm, practical words help. A pediatrician can be a good first stop, and they can refer to a dermatologist when needed.

Section recap: Testing relatives is not helpful for acne, but sharing family history with a pediatrician or dermatologist is. Watch for scarring and for effects on a teen’s mood.

Privacy, insurance and genetic discrimination laws

Many parents worry about who can see a DNA result. Laws in both the US and Canada offer protection, but the details differ.

United States: GINA

The Genetic Information Nondiscrimination Act (GINA) became law in 2008. It protects against discrimination based on genetic information in two areas:

• Health insurance (Title I)
• Employment (Title II)

GINA has important gaps:

• It does not cover life, disability or long-term care insurance.
• It does not apply to employers with fewer than 15 employees.
• The US military may use genetic information in employment decisions.

Some states have added their own laws to fill these gaps.

Canada: the Genetic Non-Discrimination Act

Canada passed the Genetic Non-Discrimination Act in 2017. Under the Act, no one can require a person to take a genetic test as a condition of goods, services or a contract. The Act also bans requiring people to share test results. It bans collecting, using or sharing a person’s results without their permission.

In 2020, the Supreme Court of Canada upheld the law in a 5-4 decision. The Court’s summary gives an example. Insurers cannot make people get tested to obtain life insurance. Penalties can reach $1 million in fines and up to five years in prison.

Practical privacy steps

Step	Why it helps
Review the privacy settings in any DNA testing account	Controls who can see the data
Check whether research consent was given	Research use can usually be reviewed in account settings
Learn the company’s data-deletion process	Lets a person remove data they no longer want stored
Think before sharing results with family members	Relatives share some of the same DNA

A lawyer or a genetic counselor can answer questions about a specific situation.

Section recap: In the US, GINA covers health insurance and most employers, but not life insurance. Canada’s law offers broader protection against forced testing and disclosure.

Frequently asked questions

Will a person with an “increased likelihood” result get severe acne?

Not necessarily. The best DNA score explains fewer than 6 out of 100 parts of acne risk. Many people with a higher score never get severe acne, and many with a typical score do. A clinician’s exam matters far more than the report.

Will a child inherit severe acne from a parent who had it?

A child’s chance is higher than average, but not certain. Studies show that a parental history of acne is linked with roughly 3 times the odds of acne at the group level. No published figure gives a child’s exact lifetime risk. Family history is a reason for early care, not a guarantee.

Will an acne DNA result affect health or life insurance?

In the US, GINA bars health insurers from using genetic information. It does not cover life, disability or long-term care insurance. In Canada, the law bars anyone, including insurers, from requiring a genetic test or its results.

Can an employer find out about a DNA result?

In the US, GINA bars employers with 15 or more employees from using genetic information. Smaller employers and the military are not covered in the same way. In Canada, no one can require a person to disclose genetic test results.

Is a second opinion worth getting?

Yes, if acne is severe, scarring, or not improving. The AAD guideline recommends isotretinoin for acne that is severe, scarring or not responding to standard treatment. A second dermatologist can confirm whether that step makes sense. A genetic counselor can help with questions about a DNA report.

Summary

• Severe acne runs in families. A twin study traced about 4 out of 5 parts of the differences in acne to genes.
• It is polygenic. Large gene studies have found 46 linked spots in the DNA, many tied to follicle biology.
• DNA scores predict poorly. The best one explains fewer than 6 out of 100 parts of acne risk, and it was built in European-ancestry groups.
• A consumer “Severe Acne” report is an estimate, not a diagnosis.
• Guideline-based treatment matters more than a DNA score, and isotretinoin is recommended for scarring acne.
• Newer US approvals include CABTREO (2023), WINLEVI (2020), AKLIEF (2019) and SEYSARA (2018). Isotretinoin is controlled through iPLEDGE.
• GINA and Canada’s Genetic Non-Discrimination Act protect genetic information, with different limits.

For more articles on inherited conditions, see the Genetic Diseases category.

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

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5. Brinks AL, Needle CD, Perez OD, Shapiro J, Lo Sicco KI, Occidental MA, Tsirigos A, Petukhova L. The Polygenic Architecture of Human Diseases Affecting the Hair Follicle. Journal of Investigative Dermatology. 2026;146(3):602-612 (epub 2025-10-25). doi:10.1016/j.jid.2025.09.012. PMID: 41137822. https://pubmed.ncbi.nlm.nih.gov/41137822/
6. National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), NIH. Acne (health topic overview). https://www.niams.nih.gov/health-topics/acne
7. Reynolds RV, Yeung H, Cheng CE, et al. Guidelines of care for the management of acne vulgaris. Journal of the American Academy of Dermatology. 2024;90(5):1006.e1-1006.e30. doi:10.1016/j.jaad.2023.12.017. PMID: 38300170. https://pubmed.ncbi.nlm.nih.gov/38300170/
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11. U.S. Food and Drug Administration. Drugs@FDA: original approvals of CABTREO (NDA216632), WINLEVI (NDA213433), AKLIEF (NDA211527), SEYSARA (NDA209521) and ACCUTANE (NDA018662). https://www.accessdata.fda.gov/scripts/cder/daf/index.cfm?event=overview.process&ApplNo=216632
12. Health Canada. Drug Product Database entries for CABTREO, WINLEVI, AKLIEF and isotretinoin brands. https://health-products.canada.ca/dpd-bdpp/
13. U.S. Food and Drug Administration. Isotretinoin capsules prescribing information: boxed warning, indication and iPLEDGE REMS requirements (openFDA drug label). https://api.fda.gov/drug/label.json?search=openfda.generic_name:isotretinoin
14. National Human Genome Research Institute (NHGRI), NIH. Genetic Discrimination (Genetic Information Nondiscrimination Act of 2008, Public Law 110-223). https://www.genome.gov/about-genomics/policy-issues/Genetic-Discrimination
15. Government of Canada. Genetic Non-Discrimination Act (S.C. 2017, c. 3); Supreme Court of Canada. Reference re Genetic Non-Discrimination Act, 2020 SCC 17. https://laws-lois.justice.gc.ca/eng/acts/G-2.5/page-1.html ; https://www.scc-csc.ca/judgments-jugements/cb/2020/38478/
16. 23andMe Blog (2021-10-20, company source). New 23andMe+ Premium Report on Severe Acne. https://blog.23andme.com/articles/new-23andme-report-on-severe-acne

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Last updated: 2026-10-04

Author: Genelumen editorial team. This article aggregates 16 sources (tier 1=12 / tier 2=3 / tier 4=1). They include the NIH’s NIAMS and NHGRI, the U.S. FDA and Health Canada’s Drug Product Database. They also include American Academy of Dermatology guidelines, Canadian federal law, the Supreme Court of Canada and PubMed-indexed studies.

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/severe-acne-genetics-family-history-japan