Basset Fauve de Bretagne POAG research

Update : earlier in the year, I rustled up a number of individual owners of BfdB aged over eight – and with no eye problems – to provide DNA and to go to the Animal Health Trust to have an examination. The AHT also went into the ” bank” of saliva samples provided by BfdB for other reasons.

James Oliver was able to tell me when I was there with my ” over eights” that they did not show the mutation for POAG, as expected as their eyes were clear too. His paper has now been written, the ( USA) mutation has been identified, and should any BfdB develop this eye disease in future the AHT can advise further. RESULT !

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POAG is the acronym for ” Primary Open Angle Glaucoma”, which like epilepsy ( q.v) is much more common in the PBGV breed than our Basset Fauve de Bretagne. However, in 2014 POAG was diagnosed in two fauves, littermates, bred in the USA from parents who were imported from French and German kennels.

If you google any of the Petit Basset Griffon Vendeen Clubs you will soon discover that, after twenty years of trying, they have a new DNA test for this condition. Via The Animal Health Trust, and using the good offices of Dr Peter Bedford and keen breeders and owners, the breed can go beyond testing hounds to see if they have developed the condition, which was all they could do until now. Hordes of breeders and owners have attended annual  specialist eye testing, and removed affecteds and potentially their parents from breeding as these are identified. They can now spend a paltry £48 on a hound with no symptoms of this disease at an early stage and discover before breeding whether it will become affected later in life or is a carrier for the condition. This is a huge step forward for the Petit breed, as once carriers are identified – so they can never be bred to another carrier or affected -no more cases of POAG will be produced.

So, what is POAG? Its a rather nasty glaucoma, as affected dogs can go blind if their owner is not completely on the ball, measuring eye pressures at regular intervals, often needing to deliver eyedrops on a daily basis if there is a concern. The worst case scenario is that the affected hound will lose one or both eyes. For breeders, it is a ” late onset” condition, meaning a Petit will have often reached the end of its breeding life before succumbing to glaucoma aged six to nine. If you think about it, this makes it a disease which has been almost impossible to remove from the gene pool as many healthy- appearing animals will have been  bred from long before symptoms arise. We are told that other countries say it is impossible to find a UK bred Petit without risk lines in its pedigree – whether this is true or not, it shows how difficult the condition was to work around before the DNA test.

The USA Fauve Club was pro active in doing something about these first cases, which presented themselves at age six in the two affected littermates.  First it was correctly diagnosed, then DNA samples were taken and posted to the Animal Health Trust here in the UK, where they were very interested to receive it. Within weeks their researchers had made a good start on identifying where in the canine genome the gene for any POAG in  the BfdB might be found.

The President of the USA BfdB Club approached me and asked if I would present the following letter from the AHT’s Dr Mellersh and ask if the Committee would assist with their research, which as a committee member I did on 8th February. You will need to ask the Secretary what the outcome of the vote was. As with any committee decision I cannot discuss decisions out of meeting and must also comply with a committee undertaking not to contact Dr Mellersh or the AHT myself. The Committee is aware that I will talk about this condition on my own private website, hence this blog.I do understand that it would be completely unreasonable to “scare” owners, particularly pet owners, into thinking their hound might suddenly go blind, as this could not be the case. However, appealing to our intelligent community to help colleagues in another country where they do have the condition is what the AHT is doing – NOT saying we have a problem in the UK with our own breed.

The text of Dr Mellersh’s letter,  prefixed by a statement from the USA Club president and which is addressed to all BfdB groups and Clubs cascaded via the USA BfdB Club, is as follows:

LATEST Findings on POAG Research – Requesting DNA Samples

I have received an update from Dr. Cathryn Mellersh of the AHT on the glaucoma disease process (POAG) recently found in the Basset Fauve de Bretagne here in the USA. I have pasted below her update, and the latest findings, with a request for worldwide help in this research by submission of DNA samples. Ideally the the DNA should come from as wide a range of dogs as possible… so, for example, dogs from the same litter are not as useful to them as dogs with different parents. If you have a Fauve, aged 8 yrs or older, who is NOT affected with POAG, please consider submitting a DNA sample to the Animal Health Trust for the continuation of research.
In addition of course, any Fauve, of any age, who IS affected by POAG would have DNA that is helpful to their research.

The Basset Fauve de Bretagne Club of America has pledged to do all we can to help and support this cause, and it is our hope that other international clubs/communities will join us in this effort.  
Thank you, Carolyn DeFiore, President, BFdBCA

From Dr. Cathryn Mellersh, Animal Health Trust:

Geneticists at the Animal Health Trust (AHT) have found a mutation in the DNA of Basset Fauve de Bretagnes affected with primary open angle glaucoma (POAG) that might be the cause of POAG in the breed. It must be stressed at this stage that this result is unconfirmed and requires further validation.

To be able to confirm this finding we need to screen the DNA of additional Basset Fauve de Bretagnes that are unaffected by POAG, to confirm that none of these dogs carry two copies of the mutation. DNA from additional affected dogs would also be extremely useful but obviously harder to provide.

We need DNA from dogs over the age of 8 years that have not developed POAG.

As a way of thanking owners who help us follow up our findings we will provide a DNA test certificate, free of charge, for up to 100 dogs that contribute to this stage of the research. The certificates will be provided once the mutation has been confirmed to be the cause of POAG in this breed and a DNA test has been launched. Dogs that are able to contribute to our research must be:

· 8 years old or over
· Free from any signs of POAG.

If this mutation proves not to be the cause of POAG the AHT will retain the DNA samples and use them to validate additional mutations we find, with the offer of a free DNA testing certificate remaining valid until we manage to identify the true causal mutation and develop a DNA test.

The work is being carried out by James Oliver, who is a veterinary ophthalmologist and undertaking a PhD investigating the genetics of glaucoma in dogs.

To request a free DNA collection kit please email Bryan McLaughlin (bryan.mclaughlin@aht.org.uk). Bryan will send kits to the first 100 owners to contact him. Please only request up to 3 kits per person.

Many thanks for your help with this important research.

Cathryn Mellersh
Head of Canine Genetics
Animal Health Trust
Cathryn.mellersh@aht.org.uk

Its really unusual to be in a situation as a breed where we have no known cases in GB, but can volunteer to help with research which potentially could give us a DNA test should we ever need it – but much rather this fortunate position than the alternative, as I am sure Petit owners would attest.

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