Xeroderma pigmentosum is a condition that affects the skin and eyes due to sensitivity to UV from the sun and light. Symptoms typically develop in early childhood and include severe sunburn, skin blistering and skin discoloration; light sensitivity in the eyes and cornea inflammation. There is also an increased risk of skin cancer and non-cancerous skin growths. Some peope also develop progressive neurologic problems, depending on the gene variations they inherit. Life expectancy can be shortened, often due to cancer or neurologic complications. Treatment involves sun avoidance and regular skin checks. Several genes are known to cause xeroderma pigmentosum and symptoms vary depending on the gene involved. Variations in the XPA gene specifically cause xeroderma pigmentosum complementation group A.
As humans we have about 23,000 genes. These genes are like tiny instruction manuals that influence our health, growth and development. We inherit half of our genes from our biological mum and the other half from our biological dad. These genes are lined up on structures called chromosomes. Most of us have 23 pairs of chromosomes. The first 22 pairs are called autosomes and for the most part - these are the same among men and women. The 23rd pair determine our sex - two X chromosomes for a female and one X and one Y chromosome for males.
xeroderma pigmentosum (complementation group A) is known as an autosomal recessive condition. For autosomal recessive conditions, if a person has a variation in one copy of their gene, they are a carrier. This means that they are healthy because they also have a working copy of the gene. But, they can still pass their non-working copy to their child.
If the other parent also happens to be a carrier of the same gene, there is a 25% (1 in 4) chance that they both pass this gene variation on to their child — and as such, have a child affected by the disease.
If both parents are carriers of xeroderma pigmentosum (complementation group A), there's a one in four chance that their children could develop symptoms.
Carrier testing is like a checkup for your genes. It tests to see if you carry a gene variation that could cause a serious genetic disease in your child. Eugene offers an inclusive genetic carrier screening panel that includes xeroderma pigmentosum (complementation group A), but there's a total 301 conditions that can be tested.
Eugene's carrier test is a clinical grade test that can be done from the comfort of your own home — it's just a saliva test. You're also paired with a genetic counsellor who provides mindful support and guidance every step of the way.Learn more about carrier screening
The biggest benefit of screening for xeroderma pigmentosum (complementation group A) is that it can help future parents understand their reproductive risk so they can be ready and empowered to make more informed decisions. If neither partner are carriers, it provides reassurance and peace of mind that the risk of having a child with a genetic disease is low.
Since 90% of children that have a recessive genetic disease like xeroderma pigmentosum (complementation group A) had no previous family history of it, it often feels completely out of the blue for the parents. Getting screened is a way to know this risk in advance, which can help familes manage or even prevent the disease in the first place.