Short answer · Medically reviewed summary · Last updated: 2026-04-07
Xeroderma Pigmentosum is a rare, inherited genetic condition characterized by an extreme sensitivity to ultraviolet (UV) radiation from sunlight, which leads to a significantly increased risk of developing skin cancers and ocular complications. Understanding the Condition Individuals living with Xeroderma Pigmentosum lack the ability to effectively repair DNA damage caused by UV rays. Because the body cannot fix this cellular damage, it accumulates over time, leading to severe sunburns, blistering, and the early development of skin cancers, often starting in childhood.
What is Xeroderma Pigmentosum
What is Xeroderma Pigmentosum? Plain-language, medically reviewed definition plus the lived reality told by patients.
Xeroderma Pigmentosum is a rare, inherited genetic condition characterized by an extreme sensitivity to ultraviolet (UV) radiation from sunlight, which leads to a significantly increased risk of developing skin cancers and ocular complications.
Understanding the Condition
Individuals living with Xeroderma Pigmentosum lack the ability to effectively repair DNA damage caused by UV rays. Because the body cannot fix this cellular damage, it accumulates over time, leading to severe sunburns, blistering, and the early development of skin cancers, often starting in childhood. Beyond the skin, Xeroderma Pigmentosum frequently affects the eyes—causing inflammation and tumors on the cornea and eyelids—and can sometimes involve the nervous system, leading to developmental delays or hearing loss in certain subtypes.
Subtypes and Prevalence
The condition is classified into eight complementation groups (XP-A through XP-G, plus a variant form, XP-V), determined by which specific gene involved in the DNA repair process is mutated. Xeroderma Pigmentosum is quite rare, with an estimated global prevalence of approximately 1 in 1,000,000 in the United States and Europe, though it is more common in populations with higher rates of consanguineous marriage, such as in parts of Japan and North Africa.
Who is Affected?
Xeroderma Pigmentosum affects males and females equally and is inherited in an autosomal recessive pattern, meaning a child must inherit a mutated gene copy from both parents. Symptoms typically manifest in early childhood, often appearing as extreme sensitivity to even minimal sun exposure. Unlike typical photosensitivity disorders, the defining feature of Xeroderma Pigmentosum is the molecular inability to repair nucleotide-level DNA damage, which distinguishes it from conditions like solar urticaria or porphyria.
Medical Disclaimer: This information is for educational purposes only and does not constitute professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition.
References
- NIH Genetic and Rare Diseases Information Center (GARD)
- Orphanet: The portal for rare diseases and orphan drugs
- Online Mendelian Inheritance in Man (OMIM)
- Xeroderma Pigmentosum Society (XPS)
