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Breakthrough
in detection of copper toxicosis
Copper Toxicosis, the hereditary liver disease which has
been described as the scourge of the Bedlington
Terrier, may be eradicated from the breed thanks to a startling
new scientific breakthrough announced by the University of Utrecht
in the Netherlands.
The official announcement of scientists isolation of the
defective part of the genome responsible for the disease was
made at a special meeting held at the Kennel Club last Friday,
involving representatives of the three Bedlington Terrier breed
clubs, working Bedlingtons, and the Liver Malfunction Committee,
who have spent the past twenty years instigating research and
testing into the disease, and officials from the KCs own
Genetic Testing Group.
The meeting heard from Jeff Sampson, the KCs Genetics
Co-ordinator, who stated that, using the Utrecht data, it would
take just weeks to devise an effective DNA test
for Bedlington Terriers, using blood samples, to screen individual
dogs for the inherited disease.
The new, definitive test would be able to indicate which dogs
were Carriers, Positives or Clears,
and the data from each test could be included on registration
paperwork.

Photo
by John D Jackson
Bedlington Terriers being judged by OUR DOGS John Holden at
Darlington championship show last year.
They are one of the breeds which has benefitted from the research.
Establish
At this stage, the tests will be voluntary, but breeders will
be urged, via the breed clubs, the KC and the Liver Malfunction
Committee to have their dogs tested, thus to establish breeding
bloodlines free of Copper Toxicosis.
The meeting and, indeed, the isolation of the rogue gene marks
the culmination of twenty years hard work and perseverance
on the part of the Liver Malfunction Committee who, for many
years, were the voice in the wilderness when trying
to combat the disease which was literally the scourge of the
Bedlington Terrier.
The committee was formed by a group of concerned individuals
all Bedlington breeders and exhibitors in 1982
who had become aware of the growing problem with Copper Toxicosis
in the breed. The prime movers behind the formation of the
committee were Fiona Craig and Celia Taylor, together with
Stuart & Angela Yearley and others.
The committee wanted to combat the disease head-on and eradicate
it from the breeds various bloodlines.
Initially, the research into the disease was conducted at
Cambridge Universitys Veterinary School, under the direction
of Mike Herrtage, who now is a representative of the KC/BSAVAs
own Genetics Testing group.
In those days the tests involved liver biopsies and, in some
sad cases, autopsies on affected dogs. This research enabled
Herrtage and his team to devise a reasonably reliable although
very expensive test to isolate the affected bloodlines.
Stuart Yearley, chairman of the LMC, says: It took time
to convince the majority of breeders of the need to conduct
these tests. Its understandable that people dont
like to admit that they might be breeding dogs that are affected
in this way. Many in the breed ignored us for a long time
and took a lot of persuasion to accept what we were doing.
Eventually, we attached ourselves to the Bedlington Terrier
Association and this, if you like, was a way of validating
what we were doing.
The initial survey conducted at Cambridge indicated
that over 30% of dogs were affected and the majority of the
remainder were carriers. But through the testing programme,
which we eventually managed to convince breeders to take up,
a small number of clear animals were identified
with an accuracy rate of 98.5%.
The Kennel Club refused to record any testing details in pedigrees
and registrations until a 100% effective test could be devised.
However, the University of Michigan, partly funded by the
LMC, created a Genetic Marker test which made screening more
accessible. Through the new screening programme over 600 Bedlingtons
in the UK alone were tested.
It was then that the designation of 1 for a clear
gene was created and 2 for an affected gene. Thus
the best definition for a dog would be 1.1 for a Clear
dog, whereas 1.2 would be a Carrier and
a 2.2 dog would normally be a fully affected dog.
Last year, using the Michigan test as a basis for their research,
the University of Utrecht, Holland, devised their own test
and managed to isolate the defective part of the genome responsible
for Copper Toxicosis and the results of this were announced
to the KC meeting just weeks later in January 2002.
OrganiseThe meeting of the KC and breed clubs was arranged
some time ago to try to organise a timescale for blood testing
for Copper Toxicosis, says Stuart Yearley, However,
we were hopeful that we might have an announcement to make
from Utrecht, and indeed we did. We hope that the test, once
devised, will be licensed for use in the UK by the Animal
Health Trust.
It was agreed at the meeting that it would be necessary to
have a big voluntary take-up of the test by breeders
over the next two years before it was feasible to consider
what further action should be taken, and that this proposal
would be conveyed to representatives respective breed
clubs for discussion. It was envisaged that all such test
results would be monitored and could be made available for
inclusion in registration documentation. Stuart continues:
We also agreed that DNA Profiling for identification
purposes should be included on registration documents. This
represents a major step forward and is very positive that
everybody is in agreement over this.
Breeders and exhibitors should be grateful to the efforts
of the Liver Malfunction Committee over the past twenty years.
In that time, the Committee raised over £10,000 to subsidise
tests for those breeders who could not afford to pay for their
dogs to be tested, and to help fund vital research
such as that at Utrecht which helped to speed up the
process in isolating the affected part of the genome.
Funds were raised by raffles, tombolas, exemption shows organised
by the committee and some very generous individual donations.
Its mainly through the work of the little
old ladies that weve got to where we are today,
says Stuart Yearley. Its good for the breed and
hopefully, one day, we will see 100% clear bloodlines and
the scourge of Copper Toxicosis will be eliminated forever.
Its a good start to the year!
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