There are several conditions associated with the NR2E3 gene, which include enhanced S-cone syndrome and retinitis pigmentosa 37. NR2E3-related conditions can be inherited in either an autosomal recessive (AR) way, which means both copies of the gene need to have a variation for someone to be affected; or in an autosomal dominant (AD) way, where a variation in only one copy of the gene is enough to cause symptoms.
Enhanced S-cone syndrome (ESCS) is autosomal recessive and causes increased numbers of S-cone photoreceptors in the retina - the part of the eyes that responds to light. Individuals with ESCS have increased sensitivity to blue light, experience progressive vision loss and night-blindness. Vision loss can be slowed down with treatment, however this condition cannot be cured.
Retinitis pigmentosa 37 (RP) can be either autosomal recessive or dominant and also affects the retina. The first sign of RP is often difficulty seeing in low light settings (night blindness), which usually occurs during childhood or adolescence. Vision loss is progressive and continues over years or decades. The severity of symptoms and age of onset varies by individual.
|Alternative Names:||ESCS, enhanced S-cone syndrome, retinitis pigmentosa 37|
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.
NR2E3-related conditions (including enhanced S-cone syndrome) 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 NR2E3-related conditions (including enhanced S-cone syndrome), 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 NR2E3-related conditions (including enhanced S-cone syndrome), 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 NR2E3-related conditions (including enhanced S-cone syndrome) 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 NR2E3-related conditions (including enhanced S-cone syndrome) 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.