PRA

GR_PRA1 tests Statistics up to 22nd November 2012

GR_PRA1Total number of dogs testedAffectedCarrierUnaffected
All Countries958483869
UK318223293

Re-Testing of Samples For GR-PRA2

As you may be aware we have recently discovered an additional genetic change that has been interfering with a small number of results for DNA testing for GR-PRA2. This second genetic change was not identified in the original research into GR-PRA2 because it is rare compared with the other normal form of the gene, and it was only when we began routine testing that the larger number of samples available revealed this variant.

We have re-tested all the samples submitted for GR-PRA2 DNA testing using a revised protocol which our research scientists have developed and which avoids the problem that we had identified. Only one original swab sample did not give sufficiently good data on re-testing for us to be confident of calling a result and we have asked the owner of this sample to submit further swabs for us to re-test; this further testing will be carried out free-of-charge.

The additional genetic change which we had identified had the effect of masking some normal copies of the gene in testing. This had two implications for the test results sent out:

1) 7 dogs were originally classified as affected, but on re-testing could be seen to have one GR-PRA2 copy of the gene and one normal copy of the gene and have therefore been re-classified as carriers

2) we were unable originally to obtain a result for 7 dogs: these dogs have now been confirmed as clears.

We would like to thank all the Golden Retriever breeders and owners who have sent in samples to us for their patience whilst we resolved this issue. All DNA testing for GR-PRA2 at the Animal Health Trust now uses our revised protocol, avoiding the problem caused by this second genetic change.

AHT December 2012

AHT GPRA2 Statement

AHT Statement December 2012 (text above)