Xeroderma pigmentosum, commonly known as XP, is an inherited condition characterized by an extreme sensitivity to ultraviolet radiation (UVR), which is present in sunlight and may also be found in some types of artificial lighting. This condition mostly affects the eyes and areas of skin exposed to the sun. Xeroderma pigmentosum is associated with an increased risk of UVR-induced cancers. People with this condition often experience premature aging. Some affected individuals also have problems involving the nervous system. The signs of xeroderma pigmentosum usually appear in infancy or early childhood. About half of affected children develop a severe sunburn after spending just a few minutes in the sun. The sunburn causes redness and blistering that can last for weeks. However, some children with xeroderma pigmentosum can tan normally. By age 2, almost all children with xeroderma pigmentosum develop freckling of the skin in sun-exposed areas (such as the face, arms, and lips); this type of freckling rarely occurs in young children without the disorder. In affected individuals, exposure to sunlight often causes dry skin (xeroderma) and changes in skin coloring (pigmentation). This combination of features gives the condition its name. People with xeroderma pigmentosum are 10,000 times more likely to develop non-melanoma skin cancer and up to 2,000 times more likely to develop melanoma skin cancer compared to individuals without this condition. The types of skin cancer that can develop include basal cell carcinoma, squamous cell carcinoma, and melanoma. Most commonly, the first skin cancer appears in affected individuals before age 10. Without protection from the sun and other sources of UVR, most people with xeroderma pigmentosum develop multiple skin cancers during their lifetime. These cancers occur most often on portions of the body that are exposed to the sun, including the face, the lips, the eyelids, the surface of the eyes, the scalp, and the tip of the tongue. Studies suggest that people with xeroderma pigmentosum may also have an increased risk of some internal cancers, including brain tumors, thyroid cancer, and blood cancers. Additionally, affected individuals who smoke cigarettes have a significantly increased risk of lung cancer. The eyes of people with xeroderma pigmentosum may be painfully sensitive to UVR (photophobia). If the eyes are not protected from UVR, they may become bloodshot and irritated, and the clear front covering of the eyes (the cornea) may become cloudy. In some people, the eyelashes fall out and the eyelids may be thin and turn abnormally inward or outward. In addition to an increased risk of cancer on the surface of the eye, xeroderma pigmentosum is associated with noncancerous growths on the eye. Many of these eye abnormalities can impair vision. About 30 percent of people with xeroderma pigmentosum develop progressive neurological abnormalities in addition to problems involving the skin and eyes. These abnormalities can include hearing loss, poor coordination, difficulty walking, movement problems, loss of intellectual function, difficulty swallowing and talking, and seizures. When these neurological problems occur, they tend to worsen with time. Individuals with xeroderma pigmentosum may experience early menopause. Researchers have identified at least eight genetic forms of xeroderma pigmentosum: complementation group A (XP-A) through complementation group G (XP-G), plus a variant type (XP-V). The types are distinguished by their genetic cause. All of the types increase the risk of skin cancer, although some are more likely than others to be associated with neurological abnormalities.
Resource(s) for Medical Professionals and Scientists on This Disease:
RARe-SOURCE™offers rare disease gene variant annotations and links to rare disease gene literature.
GeneReviewprovides clinical information on genetic diseases, including diagnosis, treatment, and genetic counseling.
About Xeroderma pigmentosum
Many rare diseases have limited information. Currently, GARD aims to provide the following information for this disease:
Symptoms:May start to appear at any time in life.
Cause:This disease is caused by a change in the genetic material (DNA).
Organizations:Patient organizations dedicated to this rare disease are available on GARD, or you may contact a GARD Information Specialist for additional information.
Xeroderma pigmentosum is caused by genetic mutations, also known as pathogenic variants. Genetic mutations can be hereditary, when parents pass them down to their children, or they may occur randomly when cells are dividing. Genetic mutations may also result from contracted viruses, environmental factors, such as UV radiation from sunlight exposure, or a combination of any of these. Learn more about genetic diseases from the National Library of Medicine (NLM).
If you suspect you may have this disease, you may want to start collecting your family health history. Information such as other family members who have had similar symptoms, when their/your symptoms first appeared, or exposures to any potential disease-causing environmental factors should be discussed with your medical team. This tool from the Surgeon General can help you collect your family health history.
Can diseases be passed down from parent to child?
A biological parent can sometimes pass down genetic changes, called mutations, that cause a disease or increase the chances of developing it. This is called inheritance. Knowing if other family members have had the disease, also known as your family health history, can give your medical team important information. The Surgeon General offers a tool to help you collect your family health history.
Autosomal Recessive
Autosomal means the gene involved is located on one of the numbered chromosomes. Recessive means that a child must inherit two copies of the mutated gene, one from each biological parent, to be affected by the disease. A carrier is a person who only has one copy of the genetic mutation. A carrier usually doesn't show any symptoms of the disease.
If both biological parents are carriers, there is a 25% their child inherits both copies of the mutated gene and is affected by the disease. Additionally, there is a 50% chance their child inherits only one copy of the mutated gene and is a carrier.
Symptoms of this disease may start to appear at any time in life.
The age symptoms may begin to appear differs between diseases. Symptoms may begin in a single age range, or during several age ranges. The symptoms of some diseases may begin at any age. Knowing when symptoms may have appeared can help medical providers find the correct diagnosis.
Prenatal Selected
Before Birth
Newborn Selected
Birth-4 weeks
Infant Selected
1-23 months
Child Selected
2-11 years
Adolescent Selected
12-18 years
Adult Selected
19-65 years
Older Adult Selected
65+ years
Symptoms may start to appear at any time in life.
Symptoms
The types of symptoms experienced, and their intensity, may vary among people with this disease. Your experience may be different from others. Consult your health care team for more information.
The following describes the symptom(s) associated with this disease along with the corresponding body system(s), description, synonyms, and frequency (Note: Not all possible symptoms may be listed):
57 Symptoms
57 Symptoms
57 Symptoms
Body Systems
Symptoms related to this disease may affect different systems of the body. Use the 'Filter and Sort' function to learn more about which body system(s) are affected by this disease and their associated symptom(s).
On average, it can take more than six years to receive an accurate diagnosis. Many primary care providers (PCPs) may not be familiar with rare diseases, and patients often need to visit multiple specialists or seek second opinions to get answers.
If a diagnosis remains unclear, visiting a multidisciplinary care center or university hospital may help. These centers bring together teams of specialists who can work together to evaluate symptoms and coordinate a diagnosis. This team-based approach is also helpful after a diagnosis, when managing care for rare diseases.
Because only about 5% of rare diseases have FDA-approved treatments, finding the right healthcare team to manage your symptoms and overall health is essential. People living with rare diseases often face challenges such as delayed diagnosis, limited treatment options, and difficulty accessing knowledgeable providers. Building a care team that understands your needs can make a significant difference in your quality of life.
Your Health Care Team
Why is building the right health care team important?
Building the right health care team is key to the diagnosis, treatment, and management of your long-term health journey living with a rare disease. Start by choosing a primary care provider (PCP). Your PCP will be your main point of contact and help coordinate care with other medical professionals. Your PCP may order tests or refer you to specialists. To find a PCP near you, use the Medicare provider search tool and enter your location and “Primary Care Provider.”
Seeing multiple specialists is important for people with rare diseases because these conditions often affect many parts of the body and require care from doctors with different expertise. Most primary care providers may not be familiar with rare diseases, so involving specialists can lead to a more accurate diagnosis and better care. A coordinated team approach ensures that all symptoms are addressed and that care is well-managed. It can also connect patients with the latest research or treatment options.
These specialists may help in the diagnosis, management, and treatment of Xeroderma pigmentosum:
Multidisciplinary Care Centers
Is It Time to Get a Second Opinion or Specialized Evaluation?
If you've visited your PCP, met with specialists, and undergone the recommended tests, but are still searching for a diagnosis, it may be time to visit an academic medical center or, for pediatric patients, a children's hospital. Academic medical centers and children's hospitals, often called multidisciplinary care centers, typically bring together specialists from different fields to work together on complex cases like rare diseases.
Multidisciplinary care centers may offer more coordinated care and be involved in clinical research, which may help reduce the time to diagnosis and provide access to emerging diagnostic tools. Specialists at these centers may have a deeper understanding of rare diseases and serve as a resource when you'd like a second opinion, particularly when test results or treatment plans are not delivering expected results.
Children’s hospitals and large teaching hospitals may also offer dedicated specialists and programs for pediatric patients with undiagnosed or rare diseases. These programs bring pediatric experts together in one place and may provide more coordinated care for your child.
If a diagnosis, care management, or treatment plan remains unclear despite extensive efforts by your PCP and specialists, it may be time to find a rare disease expert for your disease, if available. A rare disease expert is a medical provider that has knowledge or training on specific rare disease(s), but there may only be a few experts in your state, region, or country. Rare disease experts may work at large research or teaching hospitals, sometimes called centers of excellence. Centers of Excellence commit to sharing knowledge and best practices that can lead to improved care and treatment for individuals living with a rare disease.
You can ask your care providers for help finding an expert or use directory tools to search for experts near you. The National Organization for Rare Disorders (NORD) maintains a list of rare disease centers with experts that work together to find treatments and cures for a broad range of rare diseases. Search NORD's Center Directory to find experts near you.
Find Your Community
How can patient organizations help?
Patient organizations can help patients and families connect. They build public awareness of the disease and are a driving force behind research to improve patients' lives. They may offer online and in-person resources to help people live well with their disease. Many collaborate with medical experts and researchers.
Services of patient organizations differ, but may include:
Ways to connect to others and share personal stories
Easy-to-read information
Up-to-date treatment and research information
Patient registries
Lists of specialists or specialty centers
Financial aid and travel resources
Please note: GARD provides organizations for informational purposes only and not as an endorsement of their services. Contact a GARD Information Specialist for more information on organizations that may be dedicated to this disease. Please contact an organization directly if you have questions about the information or resources it provides.
Clinical studies are a part of clinical research and play an important role in medical advances for rare diseases. Through clinical studies, researchers may ultimately uncover better ways to treat, prevent, diagnose, and understand human diseases.
What Are Clinical Studies?
Clinical studies are medical research involving people as participants. There are two main types of clinical studies:
Clinical trials determine if a new test or treatment for a disease is effective and safe by comparing groups receiving different tests/treatments.
Observational studies involve recording changes over time among a specific group of people in their natural settings.
People participate in clinical trials for many reasons. People with a disease may participate to receive the newest possible treatment and additional care from clinical study staff as well as to help others living with the same or a similar disease. Healthy volunteers may participate to help others and to contribute to moving science forward.
To find the right clinical study we recommend you consult your doctors, other trusted medical professionals, and patient organizations. Additionally, you can use ClinicalTrials.gov to search for clinical studies by disease, terms, or location.
What if There Are No Available Clinical Studies?
ResearchMatch helps connect people interested in research studies with researchers from top medical centers across the United States. Anyone from the U.S. can register with this free program funded by NIH. Researchers from participating institutions use the database to search for and invite patients or healthy volunteers who meet their study criteria to participate.
Why may you want to consider joining the All of Us Research Program?
The All of Us Research Program is inviting 1 million people from all backgrounds across the U.S. to help build one of the most diverse health databases in history. Researchers will use the data to learn how our biology, lifestyle, and environment affect health. This may one day help them find ways to treat and prevent diseases.
ClinicalTrials.gov, an affiliate of NIH, provides current information on clinical research studies in the United States and abroad. Talk to a trusted doctor before choosing to participate in any clinical study. We recommend checking this site often and searching for studies with related terms/synonyms to improve results.
Contact a GARD Information Specialist if you need help finding more information on this rare disease or available clinical studies. Please note that GARD cannot enroll individuals in clinical studies.
Use the contact form to send your questions to a GARD Information Specialist.
Please allow 2 to 10 business days for us to respond.
ClinicalTrials.gov, an affiliate of NIH, provides current information on clinical research studies in the United States and abroad. Talk to a trusted doctor before choosing to participate in any clinical study. We recommend checking this site often and searching for studies with related terms/synonyms to improve results.
Contact a GARD Information Specialist if you need help finding more information on this rare disease or available clinical studies. Please note that GARD cannot enroll individuals in clinical studies.
Mondo Disease Ontology provides a logic-based structure unifying multiple disease resources in coordination with the Human Phenotype Ontology (HPO) and support from the NIH National Human Genome Research Institute Phenomics First Resource.
GARD uses the Human Phenotype Ontology (HPO) for standard terminology to represent a disease's phenotypic and clinical features.
