Canine
Epilepsy Studies at the Animal Health Trust
There
are many reasons why a dog may have seizures or
‘fits’.
They may be
caused by trauma, exposure to
toxins, or as a result of another, underlying disease.
If
a vet rules out these reasons for the
fits, the dog may be classified as having idiopathic epilepsy (IE),
which is
considered to be genetic.
As a
general
rule,
dogs with IE will have their first seizure between one and five years
of age.
Treatment
is usually with anti-convulsant drugs, however these are not a
cure and the aims are to reduce the frequency and severity of the fits,
improving the quality of life for the dog and its owner.
Phenobarbital
is one of the most common drugs
used, sometimes in combination with potassium bromide.
Epileptic
dogs or dogs producing epileptic progeny (especially from
different and unrelated mates) should not be used for breeding.
 At the Kennel
Club
Genetics Centre at AHT, in association with a Europe-wide collaborative
effort known as the LUPA
project, research is being
conducted to
attempt to identify causal genetic factors that contribute to the
development
of IE in the Border Collie and several other affected breeds.
The
main
aims of this work are to develop DNA tools that can be offered to
breeders to
help them make sensible breeding decisions to reduce the risk of
producing clinically
Affected dogs, and to help uncover genes that might lead to better
understanding of IE in humans. These studies require DNA
samples
from
both Affected and Unaffected dogs that can be collected as buccal
(cheek)
swabs. The DNA from the Affected dogs (known as 'cases') is
then
compared
to the DNA of the Unaffected dogs (known as 'controls') in a process
known as a
'genome-wide association study'. This scans thousands of
unique
points in
the DNA to identify regions of the genome that are consistently shared
between
dogs affected with IE, but that are not shared with unaffected
dogs. Once
an associated region has been identified, further analysis is carried
out to pinpoint
the mutation(s) that is/are contributing to the risk of developing IE.
Sample collection
for the Border Collie IE research is ongoing at the Kennel Club
Genetics Centre
at the AHT. If you would like to contribute a sample from
your
dog to the
research, scientists require samples from dogs affected with IE and
from Unaffected
dogs over the age of seven years. Unaffected dogs can be
related
or
unrelated to Affected dogs; the new approaches used for this research
mean that
it is no longer a requirement to have family-based samples.
The
AHT
provides DNA collection swab kits, free of charge, to individual owners
or
clinicians - contact Bryan McLaughlin at bryan.mclaughlin@aht.org.uk
The
Czech Border
Collie Club recently began a database
recording names of Border Collies (along
with their pedigrees) suffering from seizures. Although
this is not necessarily an indication
of inherited epilepsy in these
lines, it is a place where people can submit this sort of information
to be
viewed by anyone.
As it is
still not
know how epilepsy may be inherited in Border Collies, this information
should
be used with caution.
Following
on from
this the Border Collie Breed Council and PBHF decided to make a similar
facility available for people to
submit pedigrees of their own dogs
suffering
from seizures, no matter what the cause.
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