Statistics are usually published in the GRCA News edition that follows receipt of the stats by Ann Hubbs. You might want to watch for those numbers there and collect them as time goes on.
The statistics are incomplete as they come from Optigen, and they do not account for test samples that might be sent directly to AHT in the UK (for PRA1) and Antagene in France (for ICT). I believe that GRCA Health & Genetics Committee are working on setting up communications with those labs.
Keep in mind, that only statistics are released. Patient confidentiality is always maintained. That is why it is important for all people who test their dogs to use OFA or www.GoldenDNA.org to record their test results permanently. It will be immensely helpful for future breeders! And don’t think that people will just remember. They won’t. You need a permanent record somewhere it can be accessed easily.
The surprising results are for ICT. During the 3rd quarter of 2011: 75 dogs tested
- Normal – 25
- Carriers – 39
- Affected – 11
(52% carriers; 14.6% affected)
I think it’s safe to say that, in this case, the dogs tested first are likely the ones that owners suspect carry the gene. As the number of tested population becomes more randomized, these percentages should decrease at least somewhat. However, this has given me a heads up about testing my own dogs for this problem.
Total tested – 175:
- Normal – 157
- Carrier – 18
- Affected – 0
(about 10% carriers)
People are theorizing that this mutation occurs more often in European-based lines. So far most of the dogs tested are from those lines, so may not fairly represent the situation in US/Can lines. I have personally checked 2 bitches, one which has some conformation input, and both are normal for PRA1.
Daphne, the original prcd-affected dog, is also clear for PRA1. We DO know that more than one from of PRA can occur in the same dog. One dog (now deceased) is listed on www.GoldenDNA.org who was physically affected with PRA who is clear for prcd and a carrier for PRA1. So, we can extrapolate that the PRA which caused this dog’s physical symptoms came from a mutation that does not yet have a DNA test available. So, this dog has one copy of the mutated PRA1 gene… but also has an additional mutation which presents PRA symptoms. (won’t know if that one is recessive until we find the DNA test for it).
Total tested – 162: …
- Normal – 128 …
- Carrier – 34 …
- Affected – 0
(about 20% carriers)
This carrier percentage has remained pretty stable over the past three years. In the case of prcd-PRA comparatively few dogs have been tested who come from non-field lines (as far as I know… since I can only go from the statistics of dogs whose results have been published by their owners). So, this is not a fair representation of the general breeding population which is dominated numerically by dogs who are oriented toward conformational pursuits.