Is psoriasis passed down?
It runs in families, but not the way eye colour does. Most children of a parent with psoriasis do not develop it. A family history raises the odds. It does not set them. Evidence Evidence
What is known
- Sources cited, not yet graded
The National Psoriasis Foundation cites its own health-indicator survey for the lifetime risk of developing psoriasis. If neither parent has it, the risk is about 4 per cent. If one parent has it, the risk is 14 to 28 per cent. If both parents have it, the risk is 40 to 65 per cent. Those figures rise further if a child in the family already has psoriasis. That is about 24 per cent with no affected parent, 51 per cent with one, and 83 per cent with both. The AAD tells readers that having a parent, grandparent, sibling or child with psoriasis raises a person's own risk of getting it.
What is uncertain
- Depends on you
A figure measured across a surveyed group is not a figure for your family. The foundation's percentages come from its own health-indicator report, which has not been independently re-derived. They give no age by which the risk is resolved one way or the other.
Questions for your dermatologist
Given who in my family has this, what would you say the picture is for my children?
Saving keeps this on your device and needs JavaScript, which is off in this browser.Which relatives are worth naming when you take my history?
Saving keeps this on your device and needs JavaScript, which is off in this browser.
Is there a genetic test that would tell me?
Not one that predicts psoriasis. The condition is polygenic. Many genes each add a small amount, and some people who develop psoriasis carry none of the genes known to raise the risk. Evidence Evidence
What is known
- Sources cited, not yet graded
A genetics review records that more than 80 psoriasis susceptibility genes have been identified through linkage analysis and genome-wide association studies. It records that HLA-C*06:02, at the PSORS1 locus, is confirmed to play a role in psoriasis and is linked to disease severity, earlier onset and familial inheritance. The AAD states plainly that some people who get psoriasis do not have any of the genes known to raise the risk.
What is uncertain
- Depends on you
A linked gene is a finding about populations, not a result about you. There is no single test that confirms or rules out psoriasis. Which, if any, evaluation suits your family is a call your clinician makes, not a rule from a page.
Questions for your dermatologist
Is any testing useful here, and what would it actually tell us?
Saving keeps this on your device and needs JavaScript, which is off in this browser.Would a referral to genetics change how you would manage this for my family?
Saving keeps this on your device and needs JavaScript, which is off in this browser.
Why does psoriatic arthritis keep coming up in the same families?
Because several immune-mediated conditions share overlapping genes. That is why a dermatologist asks about relatives, and not only about psoriasis. It is a reason to give a full family history. It is not a reason to expect any of it. Evidence Evidence
What is known
- Sources cited, not yet graded
The joint AAD-NPF comorbidities guideline names several conditions that come up alongside psoriasis. It names psoriatic arthritis, heart and blood vessel disease, obesity, high blood pressure, raised blood fats and diabetes. It also names inflammatory bowel disease, uveitis, depression and anxiety. It asks clinicians to screen for several of these. A genetics review records that many of the genes linked to psoriasis sit in pathways shared with other immune-mediated conditions.
What is uncertain
- Depends on you
A condition appearing in a guideline's named list is not a diagnosis in your family. The guideline's authors report industry relationships, and it is US guidance. Neither record says which linked condition one relative or child will get, and neither sets a testing plan for everyone.
Questions for your dermatologist
Which conditions in my family are worth writing into my notes?
Saving keeps this on your device and needs JavaScript, which is off in this browser.Would you screen me for any of these because of that history, and how often?
Saving keeps this on your device and needs JavaScript, which is off in this browser.
What can I watch for in my child, and when do we see a dermatologist?
Watch without hunting. A patch of scaly, red skin that does not clear like a rash, especially one that follows a sore throat, is worth showing to a clinician. Book a visit when something is there to look at. A rash on a child has many causes, and telling them apart is a clinician job. Evidence Evidence
What is known
- Sources cited, not yet graded
The joint AAD-NPF pediatric guideline reports a link between guttate psoriasis in a child and a preceding strep throat infection. Guttate psoriasis tends to appear as small, drop-shaped spots. The guideline advises checking a child who has psoriasis for other health concerns, naming low mood, anxiety and extra weight. The AAD records that stress, skin injury, starting certain medications, cold dry weather and infection are reported triggers of a flare in general.
What is uncertain
- Depends on you
Neither record gives a step-by-step way to tell psoriasis apart from eczema or another rash by description alone. The pediatric guideline is US guidance with disclosed industry relationships. The general trigger list is not specific to children and puts no figure on how often any one trigger applies. Nothing here diagnoses a child.
Questions for your dermatologist
My child has a patch here, and it followed a sore throat. What are you looking at when you examine it?
Saving keeps this on your device and needs JavaScript, which is off in this browser.What would you want us to bring back if it changes?
Saving keeps this on your device and needs JavaScript, which is off in this browser.
What has the research not settled?
Why one person with the risk genes develops psoriasis and another does not. Genes set part of the picture. Environmental factors finish it, and exactly how is still being worked out. Evidence
What is known
- Sources cited, not yet graded
A genetics review records that a large twin study found a higher concordance in identical twins than in fraternal twins, a proband-wise rate of 0.33 against 0.17. Two people with the same genes usually still do not both have psoriasis. The review therefore records psoriasis as the product of multiple genes interacting with immune and environmental factors, not genes alone. It records heritability estimates of 67 per cent in first-degree relatives and 47 per cent in second-degree relatives in the population it studied.
What is uncertain
- Depends on you
A twin figure describes pairs of twins, not a parent and a child. The heritability estimates come from one studied population and may not carry across every population. The genetics work keeps moving, so what is written here has a date on it.
Questions for your dermatologist
Has the genetics research changed since my last visit?
Saving keeps this on your device and needs JavaScript, which is off in this browser.Where would you send me to read about the current genetics work?
Saving keeps this on your device and needs JavaScript, which is off in this browser.
Evidence behind this page
Sources
Each evidence badge opens the source and its limits. The full list stays available here.
- American Academy of DermatologyPatient education · Patient education, tier 5Independent source
- Published
- SteadySkin last checked
What this source can and cannot tell you
What this source supports
Supports that stress can trigger a psoriasis flare. Supports that skin injury - a cut, scrape, sunburn, tattoo, piercing, bug bite, or shaving nick - can trigger a flare near or at that spot. Typically this appears about 10 to 14 days after the injury. Supports that an infection such as strep throat, an earache, or bronchitis can trigger a flare, reported 2 to 6 weeks later. Supports that starting a medication - including lithium, antimalarial drugs, strong corticosteroids, or some blood pressure drugs - can trigger a flare about 2 to 3 weeks after starting it. Supports that cold, dry weather (such as winter or fall) can worsen flares, and that sunburn or spending time in air conditioning can also worsen them. Supports that smoking, or spending time around secondhand smoke, is a reported trigger. Supports that drinking daily, or more than two drinks on several days a week, can make psoriasis treatment have little or no effect. Supports that triggers differ from person to person.
What it does not support
Does not cite a specific study for its trigger list or timing windows, and does not state how many patients experience each trigger. This page displays no revision date; the date recorded here matches the same AAD psoriasis disease microsite's treatment-and-diagnosis page, checked the same day. Does not establish that avoiding a listed trigger will prevent a flare for any one person.
Claim-specific review for this source is still in progress. Only the source-level evidence and limits are shown here.
- Journal of the American Academy of Dermatology (Menter A, Cordoro KM, Davis DMR, et al.)Guideline · Regulatory / guideline, tier 1Relevant relationship disclosed
- Published
- SteadySkin last checked
What this source can and cannot tell you
Why the independence label says this: The journal is the publisher. This label refers to the author relationships disclosed for the guideline, not to the journal itself.
What this source supports
Supports that the American Academy of Dermatology and the National Psoriasis Foundation share one guideline for psoriasis in children. Supports that it covers topical, light and systemic treatment in that age group. Supports the reported link between guttate psoriasis in a child and strep throat. Supports checking a child who has psoriasis for other health problems. It names low mood and anxiety. It also names extra weight.
What it does not support
It does not judge one child. It names no product, no strength and no course length. It gives no figure for how many children get better. It is US guidance. It sets no coverage rule.
Claim-specific review for this source is still in progress. Only the source-level evidence and limits are shown here.
- Journal of the American Academy of Dermatology (Elmets CA, Leonardi CL, Davis DMR, et al.)Guideline · Regulatory / guideline, tier 1Relevant relationship disclosed
- Published
- SteadySkin last checked
What this source can and cannot tell you
Why the independence label says this: The guideline reports author relationships with industry. It is expert guidance, not independent proof for one person.
What this source supports
Supports that this guideline covers psoriasis alongside other health conditions. Supports naming psoriatic arthritis as one of them. Supports naming heart and blood vessel disease. Supports naming obesity, high blood pressure, raised blood fats and diabetes. Supports naming inflammatory bowel disease. Supports naming uveitis, an inflammation inside the eye. Supports naming depression and anxiety. Supports that it asks clinicians to screen people with psoriasis for psoriatic arthritis. Supports that it asks them to check heart risk factors. Supports naming body weight, blood pressure, blood fats and blood sugar among those checks. Supports that it asks them to screen for depression.
What it does not support
Does not diagnose a reader. Does not say which linked condition one person will get. Does not read a test result or set a personal plan. Its authors report industry relationships. It is US guidance. It does not set practice in another country.
Claim-specific review for this source is still in progress. Only the source-level evidence and limits are shown here.
- Precision Clinical Medicine (Ran D, Cai M, Zhang X)Systematic review · Clinical research, tier 2Independent source
- Published
- SteadySkin last checked
What this source can and cannot tell you
Why the independence label says this: An academic review of the genetics literature. No product is named and no manufacturer is involved in it.
What this source supports
It supports that HLA-C*06:02, the PSORS1 locus, is confirmed to play a role in psoriasis and is linked to disease severity, earlier onset and familial inheritance. It supports that more than 80 psoriasis susceptibility genes have been identified through linkage analysis and genome-wide association studies. It supports that a large twin study found a higher proband-wise concordance in identical (monozygotic) twins than in fraternal (dizygotic) twins, 0.33 against 0.17. It supports that heritability in first-degree relatives was estimated at 67 per cent and in second-degree relatives at 47 per cent in the population studied. It supports that psoriasis is a complex disease produced by multiple genes interacting with immune and environmental factors. A genetic predisposition alone does not determine who develops it.
What it does not support
It is a review, not a test and not a prediction. It gives no risk figure for one named family. It does not support a genetic test that tells a parent whether a child will develop psoriasis. Its twin and heritability figures come from a Chinese study population and may not carry across every population. It sets no screening schedule, names no treatment, and does not diagnose anybody.
Claim-specific review for this source is still in progress. Only the source-level evidence and limits are shown here.
- National Psoriasis FoundationPatient education · Patient education, tier 5Independent source
- Published
- SteadySkin last checked
What this source can and cannot tell you
What this source supports
Supports, citing the foundation's own Psoriasis Health Indicator Report, family-risk figures for lifetime risk of developing psoriasis. If neither parent has it, the figure is 4 per cent. If one parent has it, the figure is 14 to 28 per cent. If both parents have it, the figure is 40 to 65 per cent. Supports that these figures rise further if a child in the family already has psoriasis. That is 24 per cent with no affected parent, 51 per cent with one, and 83 per cent with both. Supports that lifetime risk is strongly associated with family history. Also supports that anyone can develop psoriasis regardless of family history.
What it does not support
It is patient education summarizing a foundation survey report, not the underlying study. It gives no figure for one named family and no age by which risk is resolved. It names no gene and no test. It does not diagnose anybody or set a screening plan.
Claim-specific review for this source is still in progress. Only the source-level evidence and limits are shown here.
- American Academy of DermatologyPatient education · Patient education, tier 5Independent source
- Published
- SteadySkin last checked
What this source can and cannot tell you
What this source supports
Supports that having a parent, grandparent, brother or sister with psoriasis raises a person's risk of getting it. Supports that people who have certain genes are more likely to get psoriasis. States plainly that some people who get psoriasis do not have genes known to raise the risk. Supports the immune-system account: white blood cells called T-cells are part of the immune system. In psoriasis, T-cells attack the body's own skin cells. That attack causes the body to make new skin cells much faster than usual.
What it does not support
It names no percentage of patients with a family history and no gene by name. This page displays no separate revision date; the date recorded here is the calendar year checked. It does not diagnose anybody and sets no genetic-testing recommendation.
Claim-specific review for this source is still in progress. Only the source-level evidence and limits are shown here.