Fabry disease is a disorder affecting lysosomes, which are structures in the cell that break down and recycle other molecules. Due to a deficiency of the enzyme alpha-galactosidase A, patients with Fabry disease have difficulty breaking down a fatty substance called globotriaosylceramide. Affected individuals typically begin to show symptoms in childhood, including episodes of severe pain in the hands and feet (acroparesthesia), small, dark red spots on the skin (angiokeratoma), a reduced ability to sweat (hypohidrosis), cloudiness on the cornea of the eye (corneal opacity), gastrointestinal problems, and hearing loss. Life-threatening complications such as kidney damage, heart disease, and stroke can develop. Some affected individuals have milder forms of Fabry disease that appear later in life and affect only the heart or kidneys. Enzyme replacement therapy is available and is useful in treating some of the symptoms.
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.
Fabry disease is an X-linked condition. X-linked conditions occur when there is a genetic variation on the X-chromosome. For these conditions, the sex of the parent who passes on the gene variation influences the risk for the children.
If the father is affected, all his daughters will have a variation on one of their X-chromosomes and be healthy carriers. Sons can only inherit these x-linked conditions from their mother and therefore, in this situation, will not be affected by the condition.
If the mother is a healthy carrier of an X-linked variation and has a son, there is a 50% chance that they could inherit this variant and be affected by the condition. If they have a daughter, there is a 50% chance that they will be a healthy carrier (just like her mum).
Another way of looking at this is that there is a 25% chance of having an affected son and a 75% chance that the child will not be affected by the condition.
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 condition in your child. Eugene offers an inclusive genetic carrier screening panel that includes Fabry disease, 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 Fabry disease 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 condition is low.