Sources

•  http://www.ornl.gov/sci/techresources/Human_Genome/medicine/genecounseling.shtml
• http://emedicine.medscape.com/article/1119902-overview#showall
• http://dominancerelationship.blogspot.com/2007/08/dominance-relationship.html
• http://dermnetnz.org/systemic/xeroderma-pigmentosum.html
• http://resources.mhs.vic.edu.au/science/resources/geneticssummary.htm#dominant
• http://www.patient.co.uk/doctor/Xeroderma-Pigmentosum.htm
• http://www.healthfinder.gov/scripts/searchContext.asp?topic=14486&branch=6&show=1
• http://rarediseases.info.nih.gov/GARD/Condition/7910/QnA/28106/Xeroderma_pigmentosum.aspx

 These are the websites I got all of my information from, I suggest visiting these sites for more info on XP.

I wish you all luck in dealing with XP.

How possible is it that a cure will be found?

It is very unlikely that a cure will be found because XP is a genetic disorder.  Scientists are working on a way to cure genetic diseases in general, but they will most likely only find a way to prevent the disease from spreading to future generations by removing the XP allele from the unborn child.  But, anything is possible so keep your hopes up, they might just find a cure.

What are some organizations that can help a family cope with a child's disorder?

• Xeroderma Pigmentosum Society
• XP Family Support Group

What is everyday life like? What is the quality of life?

Aside from needing to be constantly protected from UV rays it is similar to normal life.  You need to be very careful to keep out of the sun but if you acheive that you will be fine.  If you take proper precautions you will not face serious obstacles and the quality of life would be high, especially compared to most other genetic diseases.

How can the disease be treated?

• wear sunscreen (at least S.P.F. 30)
• wear long sleeves, pants, wide-brimmed hats, and eye wear specifically designed to block UV rays
• only go outdoors during nighttime
• see a dermatologist every 3-6 months
• see ophthalmologist frequently
• get yearly testing for neurological problems

What is the life expectancy of someone with the disease?

If the patient does not take the necessary precautions don't protect themselves from UV rays they may die young from skin cancer, but if they do take precautions they would have a normal life expectancy.

What are the physical symptoms of the disease?

The first symptom of the disease is freckling of the skin and reddening on the face and neck.  The second symptom is poikiloderma, or having light and dark splotches on the skin.  The third symptom is skin cancer and solar keratoses.

How is the disease diagnosed?

The disease is diagnosed within 1-2 years after birth.  A severe sunburn is a sign that the child might have XP.

What are the chances of a person with this disease passing the disease on to their offspring?

There is a 50% chance of an affected individual passing the disease on to their offspring if they mate with a carrier of the disease.

 

(rr represents an affected individual Rr represents a carrier)

There is a 0% chance of an affected individual passing the disease on to their offspring if they mate with a non-affected individual.

 

(RR represents a non-affected individual)

There is a 100% chance of an affected individual passing the disease on to their offspring if they mate with another affected individual.

	r	r
r	rr	rr
r	rr	rr

How prevalent is the disease in the population?

In the U.S.A. there is approximately 1 case for every 250,000 people.

What is the chromosomal abnormality?

XP is a choromosomal disease that affects the XPA- XPG genes that detect DNA damage caused by UV rays and remove them to make sure they aren't replicated.  In XP patients those genes have been mutated making them unable to detect and repair the DNA.

How does a person inherit this genetic disorder? Is it dominant or recessive? Is it genetic or chromosomal?

A person inherits this disease when both parents are "carriers" of the recessive allele for Xeroderma Pigmentosum (XP) or one or both parents have the disease while the other is a carrier.

XP is a choromosomal disease.

What is a Genetic counselor?

Genetic counselors help families in which a member has been diagnosed with a genetic disorder such as Down's Syndrome, Hemophilia, or Xeroderma Pigmentosum.  They provide information about the disease and discuss treatment options with the families.  They have a graduate's degrees in counseling and medical genetics.