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.

The Basset Fauve and epilepsy research – UK

Over time I have heard rumours of epileptic basset fauve de bretagne hounds, and when the opportunity came up to attend a lecture on the condition a couple of years ago of course I attended. Dr C. Mellersh is a leading geneticist at the Animal Health Trust and was speaking to an audience of Griffon Vendeen breeders, as epilepsy is becoming a problem in that breed. If you think about your French geography you will realise the two departments where our related breeds originated are very close to each other, and its certain that French hunters will have used ancestors of both breeds in the past. Could epilepsy have a common starting point, in Petits as well as Basset Fauves?

Dr Mellersh explained that the AHT collects saliva samples using a kit. The owner swabs the inside of the cheeks of each candidate hound with brushes they provide, which are then saved into sterile tubes.  They needed at least 12 samples from Petit Basset Griffon Vendeen to start research into finding which genes might be the source of the problem, and they had received enough to start their work. Additionally they needed a number of samples from elderly Petits who had never had a fit and could be considered clear of epilepsy, as their “control” group.

A couple of years passed, and this Winter  I decided to take up the genetic research angle with Brian, the research assistant  at the AHT. I wrote to him and asked if the AHT would be interested in any samples from BfdB, and if so which sorts of hounds. He asked for swabs from any hounds I could discover which had suffered from epilepsy, plus samples from hounds over the age of twelve who had never shown signs of the disease. He sent me a number of kit sets to issue to interested people.

After a calling notice on the Facebook page of the BfdB I received four requests for kits from owners of affected hounds, and a number of additional requests from owners of the suitably aged  ( 12 + and unaffected ) veterans. The AHT has asked for a full vetinerary report ( case history) on each affected hound, as epilepsy can be “idiopathic” ( no cause understood), and they will need as much information as possible before beginning their analysis in order to remove dogs with no genetic reason for epilepsy from their research group.

I’d like to stress that I have no interest in what is sent to the Animal Health Trust, and because owners and breeders are often afraid of the “stigma” of producing any dog suffering from an inherited disease this is as it should be. All I will do is issue the kits to anyone who asks for one. An addressed envelope to the AHT is inside the kit.

Brian has told me that if they have sufficient samples they will check the BfdB results against the Petit Basset Griffon Vendeen results when they are sure they have found the gene markers for the PBGVs. If we are fortunate it will indeed be the same mutation and our breed can benefit from research already done for the other breed. If it is a different mutation then it will be a much slower task to find the right genes in our breed, as we don’t really have enough samples here for the AHT to work on – they have other breeds in a much worse state and will concentrate on looking for their DNA markers.

The aim with any inherited problem is to discover a gene marker, and thereafter a DNA test to identify carriers and affected hounds across a range of specific diseases. With a DNA test carriers can either be removed from breeding, as a carrier will be unaffected, or perhaps the best specimens can be used – but only with tested clear mates, so there is no chance of producing affected progeny. From the tested offspring the best unaffected hounds who don’t carry this genetic problem could be selected to go into the next generation of breeding stock. Affected hounds can be identified before they are bred from and removed from the breeding population. Its a superb way of removing risk from any canine population. At the moment we could unwittingly breed “healthy” carriers together and produce affected progeny.

I should stress that the risk of epilepsy in the BfdB is very low indeed – to have only found four affected hounds in a population which grows, in the UK, by around 100 registrations per year and has individuals which can be expected to live for upwards of thirteen years is a very small problem, but breeders need to do all they can to keep it this way or remove it completely.

While writing about the AHT I was contacted by Anu Ahlroos – Lehmus, who works with the department at Helsinki University in Finland which identified a DNA test for epilepsy in the Lagotto Romagnola breed. They too would be interested in saliva samples from hounds affected with epilepsy as they are researching the basset breeds and have thousands of samples on file already. If anyone needs her details please let me know.

If breeders are concerned about the risk of producing epilepsy in this breed there is something which can be done right now. The Dutch club did its own research into pedigrees in the late 90s. I have had translations done from the Dutch of the original research papers, let me know if you would like a copy.  There is also a lady within the Dutch club who maintains a database showing which lines might be unsuitable to breed together as there are carriers or affected hounds in the background. As with my own experiences with PRA in another breed in the early 90s, in the days before DNA tests, the only way to keep clear of an inheritable disease would be to reduce the risk of accidentally breeding carriers together – so it would be worth an e mail to our Dutch colleagues to ensure you are not accidentally breeding in a manner which might produce affected basset fauves. You will find them very helpful.

Finally, a word about procedure. No blaming, and no whispering about show ring rivals !  This attitude is both old fashioned and counter productive. If any breed has problems then these are the responsibility of us all.  If you do  lack understanding about basic genetic principles – get to some of the excellent lectures run by the KC or the AHT and start to learn. No one ever sets out to breed a dog with a problem – its how we deal with it thereafter, with compassion and helpfulness, which brings a breed back to rights quickly. As I already know – as the group I worked with managed to eradicate a problem in another breed by working together and being open and careful with carrier lines. We trusted each other and got results. Its the only way…….