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Boxer Health
The Animal
Health Trust (http://www.aht.org.ukl)
is collecting
samples for projects seeking
to identify the
inherited genetic
mutations responsible for Boxers having an increased risk of developing
gliomas, lymphoma, mammary
tumours and mast cell tumours, respectively.
The AHT is a member of a consortium of research groups that are conducting the mammary tumour
project as part of the LUPA project (http://www.eurolupa.org/),
a 4 year initiative involving
20 veterinary schools from 12 European countries. In
contrast, the studies ongliomas,
lymphoma and mast cell tumours are AHT initiatives. With the
support of The British Boxer Club,
we applied to the Kennel Club Charitable
Trust for funding for the study on mast cell tumours, and
in September 2009 we were awarded £64,000 for a 1 year project that
began on 1st January 2010. We will seek funding for studies on gliomas
and lymphoma, respectively,
once we have collected sufficient numbers
of samples.
Mast cell
tumours
Mast
cell
tumours are the most common skin
cancer in dogs, affecting mainly
older dogs. Surgery and local radiotherapy are a cure for 70% of tumours,
but about 30% of the tumours spread and the dogs require
chemotherapy. A study in 2004 of the incidence
of mast cell tumours in
dogs diagnosed at the AHT between 1997 and 1999 identified a high prevalence in Boxers,
Golden Retrievers,
Labrador Retrievers, and Weimaraners.
At the present time, we have collected
samples from 56 Boxers affected with mast cell tumours. However, we continue to need
additional samples from Boxers with mast cell
tumours, and in particular from dogs that were diagnosed with
grade III ('high grade) mast cell tumours.
The grade III tumours are the tumours that
have a 90% chance of spreading ('metastasising'),
and if we are
able to collect a sufficient number of samples from Boxers that had grade III mast cell tumours we will
be able to attempt to identify the inherited genetic defects that cause an increased
risk of developing metastatic mast cell
tumours.
Gilomas
Gliomas (also
referred to as glial cell tumours) are
the second most frequent brain tumour in dogs, and comprise different
subtypes with a highly variable response to treatment.
Most primary brain tumours develop in older dogs,
and dog breeds with short, wide heads have a higher
risk of developing gliomas.
Clinicians in the AHT Neurology Unit have noted a disproportionately
high incidence of Boxers with gliomas,
suggesting that the breed carries genetic 'risk factors' for
this cancer.
Lymphoma
Lymphoma is
the most frequent life-threatening
cancer in dogs, accounting
for up to 20% of all tumours and affecting as many as 24 out of every 100,000
dogs. In the most common form of the disease,
cells ('Iymphocytes')
derived from the bone marrow become cancerous in one or more lymph glands where
they form tumours. Lymphoma may occur in dogs of any age,
but is most common in dogs between 6-9 years old.
If untreated, death can result within 8-12 weeks
of diagnosis. Treatment is usually with
chemotherapy, which can increase
life expectancy often to about a year, with a small proportion
of dogs surviving longer than 2 years. In 2003, the
AHT examined the occurrence of lymphoma in 20 breeds within a
UK population of 130,684 dogs, who
were insured by a pet insurance company between June 1997 and May 1998.
The investigation found that the incidence of
lymphoma in Bullmastiffs, Bulldogs and Boxers was significantly higher than in other breeds, suggesting, that these breeds
carry genetic risk factors.
Mammary Tumours
Mammary tumours
are one of the most common tumours to affect older female dogs. Around 60% of mammary tumours are benign,
and therefore many dogs can have a good outcome
if a tumour is treated with an adequate surgical procedure. Up to 50%
of bitches may present with multiple tumours affecting different glands. An increased risk of developing malignant mammary
tumours has been reported for several breeds, including Boxers, English Springer Spaniels, German Shepherd Dogs, and Cocker
Spaniels, suggesting that these breeds
carry genetic risk factors. Early spaying (before the second season) can decrease
the risk of tumours developing, and so there are more bitches affected in
countries where spaying is not common practice.
In
the long term, it is hoped that the 4 research studies will lead to the development of tests to identify
Boxers that carry the gene mutations conferring an increased risk
of developing the cancer concerned. This information will be useful to vets
as it will identify dogs that may benefit from careful monitoring for early detection of cancer,
and thereby early treatment. These tests
will also assist breeders to reduce the incidence of dogs affected with these cancers.
The research will also increase understanding of how these tumours develop, ultimately assisting
the development of new therapies.
Canine
Epilepsy Studies at the Animal Health Trust
Scientists
and clinicians at the Animal Health Trust (www.aht.org.uk) are embarking on an exciting
project to investigate the genetic basis of epilepsy in the Dog. By combining the expertise of the clinicians
to diagnose dogs with idiopathic epilepsy and state of the art genetic research capability we hope to
identify the genetic factors involved. If the research is successful the endproduct
will be a DNA test that can identify the risk of developing the condition and passing it on to future
generations.
At the
moment we are in the initial stages and the project is likely to take several years to complete but the first, and arguably
most important, step is DNA sample collection. Once sufficient samples have been collected we will analyse
genetic markers distributed evenly across the dogs genome to identify those that are shared by all affected dogs and different
from those carried by dogs that don't suffer from epilepsy. These markers will point us to the region(s) of the DNA that
contains mutation(s) that are responsible for causing epilepsy. Once we have determined the region of DNA that contains the
mutations we can undertake additional experiments to identify the mutations themselves.
If we are to be successful we need DNA samples from dogs affected with idiopathic epilepsy and
their close relatives, and also from unaffected dogs. The DNA can be provided as a blood sample (if blood is being drawn from
your dog for another purpose) or as a simple cheek swab. We would also appreciate a pedigree of all dogs that donate a sample
so we can understand how the samples we collect are related to one another. This will help us to understand the mode of inheritance
of the condition and how many genes are involved.
All
research is undertaken in complete confidence. The identity of all samples submitted to the research effort will be kept confidential
and the results from individual dogs will only be shared with the dog's owner(s), once the research has been completed.
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