Xeroderma Pigmentosum

National Organization for Rare Disorders, Inc.

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Important
It is possible that the main title of the report Xeroderma Pigmentosum is not the name you expected.

Disorder Subdivisions

  • None

General Discussion

Xeroderma pigmentosum (XP) is a group of rare inherited skin disorders characterized by a heightened reaction to sunlight (photosensitivity) with skin blistering occurring after exposure to the sun. In some cases, pain and blistering may occur immediately after contact with sunlight. Acute sunburn and persistent redness or inflammation of the skin (erythema) are also early symptoms of XP. In most cases, these symptoms may be apparent immediately after birth or occur within the next three years. In other cases, symptoms may not develop until later in childhood or, more rarely, may not be recognized until adulthood. Other symptoms of XP may include discolorations, weakness and fragility, and/or scarring of the skin.

Xeroderma pigmentosum affects the eyes as well as the skin, has been associated with several forms of skin cancer, and, in some cases, may occur along with dwarfism, mental retardation, and/or delayed development.

Several subtypes of XP (i.e., XP complementation groups) have been identified, based upon different defects in the body's ability to repair DNA damaged by ultraviolet light (UV). According to the medical literature, the symptoms and findings associated with the classic form of xeroderma pigmentosum, known as XP, type A (XPA), may also occur in association with the other XP subtypes. These include: XP, type B (XPB); XP, type C (XPC), XP, type D (XPD); XP, type E (XPE); XP, type F (XPF); and XP, type G (XPG). These XP subtypes are transmitted as an autosomal recessive trait. In addition, another subtype of the disorder, known as XP, dominant type, has autosomal dominant inheritance.

In addition to the XP subtypes discussed above, researchers have identified another form of the disorder known as XP, variant type (XP-V). As with the other XP subtypes, symptoms and findings associated with the classic form of XP may also be seen in individuals with XP-V. XP-V cells have a normal or near normal ability to repair UV-induced DNA damage (nucleotide excisional repair), however, they are defective in replicating UV-damaged DNA during the division and reproduction of cells. Although the disorder's mode of inheritance is unknown, most researchers suspect that XP-V is transmitted as an autosomal recessive trait.

Supporting Organizations

Cancer.Net

American Society of Clinical Oncology
2318 Mill Road Suite 800
Alexandria, VA 22314
Tel: (571)483-1780
Fax: (571)366-9537
Tel: (888)651-3038
Email: contactus@cancer.net
Website: http://www.cancer.net/

Genetic and Rare Diseases (GARD) Information Center

PO Box 8126
Gaithersburg, MD 20898-8126
Tel: (301)251-4925
Fax: (301)251-4911
Tel: (888)205-2311
Website: http://rarediseases.info.nih.gov/GARD/

NIH/National Institute of Arthritis and Musculoskeletal and Skin Diseases

Information Clearinghouse
One AMS Circle
Bethesda, MD 20892-3675
USA
Tel: (301)495-4484
Fax: (301)718-6366
Tel: (877)226-4267
Email: NIAMSinfo@mail.nih.gov
Website: http://www.niams.nih.gov/

Rare Cancer Alliance

1649 North Pacana Way
Green Valley, AZ 85614
USA
Website: http://www.rare-cancer.org

Skin Cancer Foundation

149 Madison Avenue
Suite 901
New York, NY 10016
Tel: (212)725-5176
Fax: (212)725-5751
Tel: (800)754-6490
Email: info@skincancer.org
Website: http://www.skincancer.org

The Arc

1825 K Street NW, Suite 1200
Washington, DC 20006
Tel: (202)534-3700
Fax: (202)534-3731
Tel: (800)433-5255
Email: info@thearc.org
Website: http://www.thearc.org

Xeroderma Pigmentosum Society, Inc.

437 Snydertown Road,
Craryville, NY 12521
Tel: (518)851-2612
Email: xps@xps.org
Website: http://www.xps.org/

For a Complete Report

This is an abstract of a report from the National Organization for Rare Disorders (NORD). For a full-text version of this report, go to www.rarediseases.org and click on Rare Disease Database under "Rare Disease Information".

The information provided in this report is not intended for diagnostic purposes. It is provided for informational purposes only.

It is possible that the title of this topic is not the name you selected. Please check the Synonyms listing to find the alternate name(s) and Disorder Subdivision(s) covered by this report.

This disease entry is based upon medical information available through the date at the end of the topic. Since NORD's resources are limited, it is not possible to keep every entry in the Rare Disease Database completely current and accurate. Please check with the agencies listed in the Resources section for the most current information about this disorder.

Last Updated:  1/12/2008
Copyright  2003 National Organization for Rare Disorders, Inc.