Update from BC Genetic Research Sub-Committee

The uptake for both L-2 HGA and HC DNA tests has been very good with numbers as follows:

The numbers for L-2 HGA tests are higher than for HC because that test was available some six months sooner than the test for HC. Breeders now generally have both tests done at the same time

There have been two changes to the way samples are taken from the time the tests were made available. Initially DNA was extracted from blood samples only but as a result of requests from owners the Animal Health Trust developed tests by way of DNA extraction from cheek swabs i.e. saliva. However the Animal Health Trust have just recently decided to discontinue testing from cheek swabs and I quote from a mail from Nigel Holmes at the AHT "the problem is that the swabs did not give good yields of DNA for testing so we had to keep going back to owners asking for further samples." So although it is less convenient for owners to have blood taken, the time taken to eventually receive a result is shorter if retests aren’t required. The reliability of those results already taken from cheek swabs is not in question.

I think that most breeders are now likely to test breeding stock, with the aim that eventually every breeder will be using hereditarily clear dogs.

One disappointment for us so far has been that the results of tests had not been getting through in to the public domain by the way of the Kennel Club website. We have been chasing the KC regarding this issue which has been having its website updated and now that the new KC website is up and running the results are being published. Looking at the website as I write the list doesn’t have the numbers that are quoted above but no doubt that will happen in due course as the figures look as though they are being updated quarterly.

We have also been working with the AHT looking at ways to improve their service to overseas countries.

The Animal Health Trust has recently been in contact saying that they can now start to look at a test for PHPV. They have had discussions with a researcher looking at a similar condition in humans (this is a similar scenario to the research path for L-2 HGA)and have asked if our owners would send blood samples to them to begin a project for PHPV. I have already forwarded an article from Cathryn Mellersh to Breed Club Secretaries for inclusion in Newsletters and Club magazines giving details of requirements. Hopefully, because we’ve essentially "been there, got the T shirt...." our owners will be more acquainted with the idea than before and not need any motivating. Please encourage owners to help out. We don’t know how PHPV is inherited so in one respect the research may not be so straight forward as HC and L-2 HGA, on the other hand because understanding is improving and there is experience to fall back on and things could happen sooner. No funding is being asked from us for this condition.

With PHPV still being prevalent we still need to keep eye testing if we are to develop a DNAtest and to avoid mating affected to affected. With information regarding the "later onset cataract" (posterior polar Subcapsular cataract) emerging, eye testing is the only way we’ll find out more. Just as a reminder, the later onset cataract has been identified in a small number of dogs, it does not affect both eyes and complete blindness is unusual. Because these cataracts usually start to present themselves after the age of 2 years and later, there is very little information regarding the Stafford as we usually eye test up to and around 18 months old.

Lesley McFadyen has given details about registering a litter bred from a carrier for L-2 HGA. Blood samples were taken from 4 weeks of age, endorsed registration documents were returned by the time the puppies were 7 weeks old. She sent the registration forms accompanied by a covering letter explaining that the puppies had been sampled for L-2 HGA. The KC held on to registration documents until the results were received, once test results had been confirmed they were forwarded to Lesley. The documents had all the relevant information regarding genetic status printed on them. She also had the registrations endorsed "progeny not eligible for registration" which she alone can lift if required. From a later litter Lesley has also experienced having registration endorsed hereditarily clear with genetic status of puppies, sire and dam printed on the documents, again in good time for puppies going to their new homes. So the KC and AHT have been up to the mark regarding fast tracking of registrations. Further details can be obtained from Lesley if required.

Ivor Keyes

--> Genetic Study for PVH