Glycogen storage disease type V (GSD-V) is a genetic condition that can affect an individual's ability to break down glycogen - a complex sugar found in muscles. The affects normal muscle function. Symptoms of GSD-V include muscle fatigue, pain, and cramping during the beginning of exercise. Frequent rest periods are usually sufficient for muscle recovery and a person can then resume exercising with little or no discomfort.
Approximately half of people with GSD-V notice that following exercise their urine appears red or brown in colour - this may suggest that the muscles and kidneys have sustained damage. In severe cases, it can eventually lead to kidney failure.
Symptoms often begin before age 20, but the disorder is rarely diagnosed before adulthood. Most individuals learn to adjust their daily activities and have relatively normal lives.
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.
glycogen storage disease type V 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 glycogen storage disease type V, 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 glycogen storage disease type V, 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 glycogen storage disease type V 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 glycogen storage disease type V 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.