Xeroderma Xeroderma PigmentosumPigmentosum

Genetic Disorder Project by Genetic Disorder Project by Morgan F. and Arkadiy F.Morgan F. and Arkadiy F.

The BasicsThe Basics

Xeroderma Pigmentosum (XP)  is a Xeroderma Pigmentosum (XP)  is a genetic disorder characterized by genetic disorder characterized by sun sensitivity. In other words, individuals sun sensitivity. In other words, individuals with XP are extremely sensitive to the with XP are extremely sensitive to the Sun’s UV rays.Sun’s UV rays.

XP is actually the name of 8 different gene XP is actually the name of 8 different gene abnormalities in 8 locations.abnormalities in 8 locations.

InheritanceInheritance

XP is inherited in an autosomal recessive XP is inherited in an autosomal recessive manner.manner.

If someone is heterozygous, they will also If someone is heterozygous, they will also be asymptomatic.be asymptomatic.

PedigreePedigree

Here is a short pedigree of a family with Here is a short pedigree of a family with XPC.XPC.

Impact on LifeImpact on Life

XP has a tremendous impact on day-to-XP has a tremendous impact on day-to-day life.day life.

Affected individuals cannot go out in Affected individuals cannot go out in sunlight because of the UV radiation.sunlight because of the UV radiation.

Special windows are required everywhere.Special windows are required everywhere.Some light bulbs must be avoided.Some light bulbs must be avoided.Constant attention to making sure that skin Constant attention to making sure that skin

is not exposed to UV light.is not exposed to UV light.

TreatmentTreatment

No “treatment” for XP exists as of yet.No “treatment” for XP exists as of yet.The best thing to do is to avoid contact The best thing to do is to avoid contact

with UV light, thus preventing skin with UV light, thus preventing skin damage. Special suits can block out UV damage. Special suits can block out UV rays.rays.

SymptomsSymptoms

Symptoms include: getting a sunburn Symptoms include: getting a sunburn quickly, freckles, dry skinquickly, freckles, dry skin

Odds for cancer increase by more than Odds for cancer increase by more than 1000!1000!

The average age for developing the first The average age for developing the first skin cancer is less than 10 years.skin cancer is less than 10 years.

Types of XP

There are several different gene mutations that cause XP. We will be focusing on the gene known as XPC.

Where XPC is

XPC is located on the 3rd chromosome, between base pairs 14,186,646 and 14,220,171.

XPC

Due to a mutation in the XPC, or Xeroderma Pigmentosum, complementation group C gene.

Codes for a protein involved in repairing damaged DNA.

DNA that is damaged by UV rays can’t be fixed.

Research

Protein Therapy Cream that stimulates “bad” proteins. Like insulin for diabetics.

Gene Therapy It is possible to replace mutated gene. Then add working copy of gene.

Other Interesting Facts

• Certain types of sunblock can’t be used by people with XP, because it absorbs light instead of reflecting it.

• Xeroderma Pigmentosum is also known as ‘Vampire Syndrome’.

Go Here for More Information

• www.xps.org• http://joomla.xpsupportgroup.org.uk/• http://www.kumc.edu/gec/support/xero

derm.html

THE END.THE END.