Archive-name: dogs-faq/medical-info/genetic-diseases
URL: http://www.k9web.com/dog-faqs/medica...-diseases.html
Last-modified: 07 Nov 1997

=======
There are nearly 100 FAQ's available for this group. For a complete
listing of these, get the "Complete List of RPD FAQs". This article
is posted bimonthly in rec.pets.dogs, and is available via anonymous ftp
to rtfm.mit.edu under pub/usenet/news.answers/dogs-faq/faq-list, via
the Web at http://www.zmall.com/pet_talk/dog-fa.../faq-list.html, or
via email by sending your message to with
send usenet/news.answers/dogs-faq/faq-list
in the body of the message.

This article is Copyright 1997 by the Author(s) listed below.
It may be freely distributed on the Internet in its entirety without
alteration provided that this copyright notice is not removed.
It may NOT reside at another website (use links, please) other
than the URL listed above without the permission of the Author(s).
This article may not be sold for profit nor incorporated in other
documents without he Author(s)'s permission and is provided "as is"
without express or implied warranty.
==========


Eliminating Genetic Diseases in Dogs:
A Buyer's Perspective

Author

by Gary F. Mason, .

Copyright 1995 Gary F. Mason. All rights reserved. However, you are
encouraged to copy and distribute this article for non-commercial use
with the following restrictions: You may not modify the article in any
way. You must include the entire article including the copyright
notice. You may not charge any fee for use, copying, nor distribution
of the product with the following exceptions: Non-profit organizations
may charge a nominal fee (not to exceed $5.00) until and unless
notified by the author this is not the case.
__________________________________________________ _______________

_QUICK INDEX: : _Introduction, Goal of the Effort , Scope of the
Effort , Description of the problem , Technical Obstacles , The Human
Component , An Approach to the Problem , Basic Education, Genetic
Information Sharing , Preregistration Testing , Show Validation ,
Modification of Breed Standards , Registration Organizations , Health
Related Organizations , Conclusion , Selected References ,
__________________________________________________ _______________

Introduction

This paper is the first product of an effort I have undertaken that
was prompted by the discovery that our five month old Scottish Terrier
suffered from Type III von Willebrand's Disease (vWD). The existence
of this genetic bleeding disorder was unknown to us until he suffered
a near fatal bleeding episode for no apparent reason. Subsequent
treatment and testing revealed that he was affected with vWD.

We were quite naive - as I suspect many people are - when we bought
our dog. Both of his parents were AKC registered, which we assumed
meant that he was a healthy dog from healthy stock. In fact, prior to
discovering his affliction, he too was registered (though we could
have registered him even after discovering his malady). We have
learned the hard way that "having papers" means very little, if
anything, about the genetic health of a purebred dog.

This experience convinced us that dogs, and those who own them, should
not have to live under the conditions dictated by genetic diseases.
This is especially true since in the main they could be prevented. Our
dog's disease has generated a lot of additional expense and worry
which might have been avoided by a properly designed and managed
breeding program. It has also become clear to us that prospective
buyers should be better educated about the world of dogs before they
make an investment that could lead to considerable extra expense, and
worse, the heartbreak of losing a beloved friend too early.

This effort has no funding or sponsorship from any organization or
other individuals. We neither breed nor show dogs, and have no plans
to do so in the future. This is a personal attempt to contribute to
the identification of, the development of tests for, and the progress
of efforts toward the eradication of genetic diseases in dogs.

This article is intended to be an objective exposition on the subject
of genetic diseases in domestic dogs. It is of the utmost importance
that the information presented be as neutral as possible so as to
encourage all interested parties to engage in productive dialog. No
attempt will be made to attach any measure of goodness or
acceptability to one view of an issue over another. It is hoped that
this approach will enable synergies to be created by joint activity
among and between parties interested in improving canine genetic
health.

While no one is intentionally being eliminated from the target
audience, the specific constituencies being addressed are breeders,
breed clubs, dog registration organizations, prospective dog
purchasers, researchers, and veterinarians.
__________________________________________________ _______________

Goal of the Effort

The goal of this effort is to provide assistance to any and all
concerned parties in hopes of making progress toward the elimination
of genetic diseases in dogs, and to generate additional interest in
that effort. To that end, it is intended to:

Educate the audience on the subject of genetic diseases in dogs.
Present a brief summary of some of the research and other activities
currently underway which are working toward the elimination of genetic
diseases in dogs. Suggest some options and approaches which can be
examined with regard to their effectiveness in reaching this goal, in
both the short term and the long term. Foster open dialog and
cooperation among and between all interested parties.
__________________________________________________ _______________

Scope of the Effort

Although primarily terrier breeds are referenced here, this effort is
not limited to any specific diseases or breeds. On the contrary, it is
intended to encompass the widest range of both. It is hoped that in
this way, the largest possible group of people will be induced to
participate, and the broadest view of the subject will be developed.

This document is a first step, and proposes to use Type III von
Willebrand's Disease in the Scottish Terrier as the example around
which to build a framework for further efforts. The current level of
knowledge about this disease is extensive, and indicates that this
disease, in this breed, presents one of the simplest cases of genetic
disease in the dog. Even if this proves to be true, vWD still offers a
formidable set of challenges to the community committed to its
eradication. But as a relatively simple example, it provides the
opportunity to"start small". The framework developed for attacking vWD
could be used as the starting point for more elaborate requirements
which would be dictated by more complex diseases.
__________________________________________________ _______________

Description of the problem

Many diseases in the domestic dog are genetic in origin. Examples are
vWD, Collie Eye Anomaly, portosystemic shunt, hemophilia, Scottie
Cramp, hip dysplasia, Legg/Calv Perthes, medial patellar luxation, and
craniomandibular osteopathy (CMO) -- the list is very long. So far,
over five hundred genetic diseases have been identified in purebred
dogs, and over a hundred in mixed breeds. They can affect
conformation, health (virtually all systems in the body are subject),
and temperament. In Scotties alone there are 36 identified genetic
diseases, with similar numbers affecting each of several other terrier
breeds.

There is a great deal of scientific research being performed on the
identification of the specific causes of genetic diseases. Because
some of the diseases exhibited by dogs are also evident in humans --
vWD is the most common human inherited blood disease -- some benefit
could derive from canine research which would be of use in pursuing
the human form of the same, or related, diseases.
__________________________________________________ _______________

Technical Obstacles

"There are no more easy problems." Anonymous

The need for accurate definition of the mode of inheritance - The
underlying causes of genetic diseases can be very complex. Efforts are
underway to identify and isolate specific genes, and combinations of
genes, related to various diseases. But it will probably be a very
long time before most have been isolated. The research process is
costly and very time consuming.

Variation in the expression of the disease - Genetic diseases which
appear to be identical across breeds may in fact be caused by
different genetic conditions. For example, vWD is believed to
exemplify one mode of inheritance in Scottish Terriers, and another in
German Shorthaired Pointers.

The absence of accurate tests - Some genetic characteristics can be
determined by observation, but more frequently tests are necessary to
identify specific genetic diseases. There are currently two tests for
vWD, one more recent (and accurate) than the other. They test for the
same constituent in the blood, but use different testing techniques.
These tests are based upon measuring the quantity of a specific
chemical in the blood, and while the test itself is very good, the
results are subject to substantial variation based upon the collection
and handling of the test samples. And there can be major variations in
the amount of the chemical present in the animal due to its condition
at the time of sample collection. Other genetic diseases depend upon
other methods for their diagnosis. These include X-ray, physical
manipulation, and other techniques. Testing for recognized genetic
markers, or the genes themselves, will offer a virtually foolproof
method for diagnosis. When a definitive test is developed for any
disease, there should be no reason to ever produce a puppy adversely
affected by that disease.
__________________________________________________ _______________

The Human Component

Any attempt to address the genetic disease problem in dogs must take
into account the human component. People breed dogs for many reasons.
While there are exceptions to every rule, most breeders of pedigreed
dogs do seem to have the animals' best interests at heart. In the
main, the production of dogs with genetic diseases today is not done
out of malice, but out of ignorance due to a of lack of historical
genetic information.

But there are other forces at work as well. Many dogs are shown at
events sanctioned by various registration groups. Breeders of winning
dogs earn the respect of their peers and others, and that respect can
lead to enhanced benefits to the breeders. Within this environment,
other benefits can also be accrued from breeding winning dogs. These
include improving the breed; gaining personal satisfaction; and
commanding higher prices for puppies bred from the winner's
bloodlines.

For genetic diseases to be eliminated, they should be given at least
as much weight as the other factors considered when breeding a dog --
principally conformation and behavioral traits. For any plan to be
successful would probably require that these benefits remain
achievable at current rates or better. The incentives provided for the
breeding of dogs without genetic diseases should be at least as good
-- probably better -- than exist today.
__________________________________________________ _______________

An Approach to the Problem

Since genetic diseases are passed to subsequent generations by parents
who contribute the causal factors contained within their own genetic
makeup, one point regarding this problem is fundamental:

The elimination of genetic diseases can only be accomplished through
selective breeding

The problems lie in determining how to identify the diseases' causal
factors in dogs; in understanding when not to breed them; and in the
implementation of selective breeding programs based upon these
factors. Some of the avenues to be investigated include:
__________________________________________________ _______________

Basic Education

First and foremost in solving any problem is ensuring that everyone
involved understands it. While genetics can be a very complex
technical subject, the basic information required to make progress
toward the elimination of genetic disease by developing an effective
breeding program is within the reach and understanding of everyone
concerned.

Breeders should understand the implications of genetic diseases
recognized as affecting their breeds, and take steps to breed only
those dogs that will minimize the propagation of unwanted
characteristics.

Prospective buyers should be made aware of the genetic diseases
related to the breed they are considering. And they should learn to
ask that test results or genetic histories for the animals they are
planning to purchase be explained to them.

Veterinarians should be able to recognize genetic diseases, and inform
owners, breeders, and prospective breeders of their presence in dogs
they examine and treat.

A general information publication on genetic diseases in all dogs
could be prepared. A cooperative effort among many breed clubs and
other interested organizations could reduce cost and gain maximum
exposure for such a product. By crossing many breeds, a single
publication could be offered to the public at many venues, including
shows for single and multiple breeds, county and state fairs, and
other events at which those interested in dogs might be expected to
attend. There are many opportunities to spread the word.
__________________________________________________ _______________

Genetic Information Sharing

Dog breeders should have access to at least the phenotypic history of
dogs in the lines that produced the prospective mates. Having this
information would help breeders to reduce the probability of the
occurrence of diseases by enabling them to determine the statistical
risks involved for propagating those diseases. The absence of this
information means breeding with no possible way of predicting the
outcome. It becomes a matter of pure chance.

One way to make this essential information available to breeders is
through an open registry, in which genetic diseases are recorded along
with the information currently available in the pedigree. Today a
stigma is often attached to a breeder and their breeding stock if this
information is made known. Rather than sharing the information, this
attitude leads to hiding it away. Open registries sponsored by breed
clubs could remove this obstacle, and facilitate improved breeding
programs. While not perfect, it can certainly help to reduce the
problem, and it is within the reach and capabilities of everyone
today.
__________________________________________________ _______________

Preregistration Testing

Testing of animals could be required before they are accepted by
registration organizations. Ideally, registration would automatically
enhance the database of genetic information available for use in
breeding programs. Very few registration organizations do this today.
Registration of litters could be withheld until test results,
histories of the parents, or both were presented to and validated by
the organizations. Registration could also carry with it the
requirement to monitor the ongoing health of the dog, and to report
the appearance of genetic diseases should they occur after
registration.
__________________________________________________ _______________

Show Validation

Participation in shows could be made dependent upon test results being
furnished to, and being evaluated by, the sponsoring organizations.
Once entered, judges could impose penalties on animals that were found
to have visible characteristics related to genetic diseases, and
forward that information to the appropriate registry.
__________________________________________________ _______________

Modification of Breed Standards

All breed standards are, in effect, artificial. They have been
developed by selectively breeding dogs over the years until they
display a certain set of desired characteristics. Sanctioning bodies
have procedures by which they can change the standards for various
reasons.

Physical conformation should be secondary to the health and
temperament of an animal. If genetic diseases are associated with
conformance characteristics in an inseparable way, breed standards
could be modified to eliminate the incentive for breeding to those
characteristics once the underlying association has been identified.
In England, through a cooperative effort between the UKC and
veterinary organizations, standards that created a propensity for
disease have been eliminated from all breeds. The Council of Europe
has also enacted resolutions that address the elimination of genetic
diseases in dogs.
__________________________________________________ _______________

Registration Organizations

Registration Organizations

Several organizations throughout the world register purebred dogs. In
general, their charters are similar, and they share the common goal of
preserving the integrity of purebred dog breeds. There are clubs that
sanction various forms of competition, and others that deal solely
with medical issues. Some of the oldest, largest, and most familiar
include:

The American Kennel Club (AKC) -- Founded in 1884, it is the oldest
and most prestigious dog registration organization. The AKC includes
in its mission: maintaining and preserving the integrity of a registry
for purebred dogs; sanctioning of dog events that promote interest in,
and sustain the process of, breeding for type and function of purebred
dogs; and taking whatever actions are necessary to protect and assure
the continuation of the sport of purebred dogs. These activities are
undertaken with the objective of advancing the study, breeding,
exhibiting, running, and maintenance of purebred dogs

The United Kennel Club (UKC) -- The UKC was formed in 1898, and today
provides an alternative to the more widely known AKC in the United
States. It performs many of the same functions: registry, shows, and
stud books. The UKC recognizes 212 breeds, including some that the AKC
does not. The UKC offers breed, obedience, agility, and hunting
trials.
__________________________________________________ _______________

Health Related Organizations

These are some of the organizations working on canine medical issues:

Institute for Genetic Disease Control in Animals (GDC) -- In an open
registry such as the one maintained by GDC, owners, breeders,
scientists, and veterinarians can trace the genetic history of any
particular dog. In order to control the increasing presence of genetic
diseases, we must know how prevalent such diseases are in the breed
and in any particular dog's bloodlines. The information about each dog
automatically becomes linked in the open registry with their
relatives. An open registry offers this information for the selection
of mates whose bloodlines indicate a reduced risk of producing genetic
disease.

The Orthopaedic Foundation for Animals (OFA) -- This organization
specializes in examining and rating dogs with specific regard to hip
dysplasia.

The Canine Eye Registration Foundation (CERF) -- An organization
dealing with canine diseases of the eyes.

Other organizations have embarked upon research and education programs
related to health and genetic diseases in specific breeds. Of all AKC
registered breed clubs, nearly three quarters have committees to
address health concerns in their breeds. Nearly half have a code of
ethics that includes health issues. Many breed clubs have either
formed or are investigating the formation of tax exempt foundations to
pursue health issues within their breeds.

Among the organizations implementing such health related programs a

The Scottish Terrier Club of America (S.T.C.A.) Health Trust Fund,
which was founded in 1994 to detect and investigate health problems;
monitor health in Scottish Terriers; participate in research to
enhance the prevention of illness; develop and advocate sound breeding
practices; foster safe and healthy environments; study and share
information that promotes better health in all purebred dogs; and
promote and encourage constructive attitudes toward health concerns.
In addition, membership in the S.T.C.A. requires that a Code of Ethics
be signed which supports the issue of genetic disease elimination in
the breed.

The Cairn Terrier Club of America (CTCA). Their Committee for Health
Related Concerns surveyed club members in 1987 for the purpose of
determining the presence and frequency of genetic diseases in the
breed. They have subsequently carried out an intensive education
program, engaged the Institute for Genetic Disease Control to provide
their open registry, and produced an award winning reference manual on
Cairn Terrier genetic diseases.

The West Highland Anomaly Task Council, Inc. (WatcH), which was Formed
in the late 1980s for the purpose of understanding and controlling
genetic diseases in West Highland White Terriers. WatcH has undertaken
programs for education, information sharing, genetic counseling, and
research. They have conducted health surveys among the WHWT
population, and created a registry to track several genetic anomalies
in Westies.

The Jack Russell Terrier Club of America (JRTCA). Unlike other
registries which register entire litters at birth, each JRT
application for registration is judged on the individual terrier's own
merits. Having registered parents does not automatically guarantee
that a terrier can be registered. A terrier is not eligible for
registration until it reaches one year of age and has attained its
adult height, dentition, and other aspects considered necessary for
full maturity. Each terrier's application for registration must be
accompanied several documents, including a veterinary certificate, a
four generation pedigree, a stud service certificate, and color
photographs which support the conformation of the dogs to the club
standard.

Many projects are underway around the world in the fight against
genetic diseases in dogs. The approach taken by organizations varies
-- some are doing scientific research while others are providing
education. Here is a sampling of some of these groups:

The Dog Genome Project -- The dog genome project is attempting to map
the entire genetic makeup of the domestic dog (there is a similar
project underway for humans). The result will be a useful tool for the
entire scientific community for the purpose of isolating the genes
causing inherited diseases. It is a collaborative study involving
scientists at the University of California, the University of Oregon,
and the Fred Hutchinson Cancer Research Center. The dog genome project
makes all research results available to the scientific community
electronically on the World-Wide Web prior to traditional publication.

Project TEACH of the Pet Health Initiative -- Project TEACH (Training
and Education in Animal Care and Health) was formed to educate about
proper animal care and methods of genetic screening. Project TEACH is
an accreditation program for individuals. All TEACH-accredited
breeders, pet shops, rescue organizations and humane societies will
screen animals for potential problems before they are sold.

AKC Canine Health Foundation -- Established by the AKC in 1995 with a
million dollar endowment. The Foundation is intended to raise money to
support health research which will benefit dogs, and will identify
areas for research and seek qualified individuals to do the research
through its Scientific Advisory committee, concerned fanciers, the
Delegate Committee on Health Research and Health Education, and
others. Since the early 1980's, AKC has been a major funder of genetic
research to benefit dogs. The AKC was the principal funder of the work
of Dr. Donald Patterson at the University of Pennsylvania to develop
the Canine Genetic Disease Information System, a database for
veterinarians.

Better Companion Breeders Association (BCBA) - Formerly the Better Dog
Breeders Association (B.D.B.A.). A public service agency devoted to
the protection of the buying public. They provide their service free
to the public, while providing members with special services to assist
them in operating their business.
__________________________________________________ _______________

Conclusion

A concerted effort is required by everyone involved with purebred dogs
if genetic diseases are to be eliminated. Science is making progress,
but the time and expense required for the research point toward this
being a long term solution. In the short term, the situation must be
addressed using the tools at hand. Open registries for purebred dogs,
administered by their respective breed clubs or independent registry
organizations, appear to be the easiest and fastest way to a short
term solution. They could also provide valuable corroborative
information to genetic disease researchers. Cooperation between dog
breeders, researchers, prospective purchasers, and purebred dog
organizations at all levels is essential if genetically healthy dogs
are to become a reality.

One thing is certain -- without the continued attention of many
people, the situation can only get worse.
__________________________________________________ _______________

Selected References

Clark, Ross D. and Joan R. Stainer, eds., "Medical and Genetic
Aspects of Purebred Dogs", Veterinary Medicine Publishing Co.,
Edwardsville, KA., 1983. ISBN 0-935078-24-X.

Heshammer, A., and Olsson, S-E., et al, "Study of heritability in
401 litters of German Shepherd Dogs"; J. AM Vet Med Assoc 174:
1012-1016, 1979.

Hutt, F.B., "Genetic selection to reduce the incidence of hip
dysplasia in dogs"; J Am Vet Med Assoc; 151: 1041-1048, 1967.

Lemonick MD, "A terrible beauty: An obsessive focus on show-ring
looks is crippling, sometimes fatally, America's purebred dogs", Time
Mag. Dec 12, 1994 :65-70

Meyers, K., Wardrop, K.J., and Meinkoth, J., " Canine vWD:
Pathobiology, diagnosis, and short-term treatment", Compendium on
Continuing Education for the Practicing Veterinarian, 1992, Vol 14(1),
pp.13-23.

Nicholas, F.W., "Veterinary Genetics", Oxford University Press, New
York, NY, 1987.

Shook, L., "The Puppy Report: How to Select a Healthy, Happy Dog",
Ballantine Books, New York, 1992, ISBN: 1-55821-140-3.

Stokol, T. & Parry, B.W., "Canine von Willebrand Disease: a review",
Aust. Vet. Practit. 23 (2), June, 1993. pp. 94 - 103. Willis, Malcolm
B. "Practical Genetics for Dog Breeders", Howell Book House, NYC, 1992
and H. F. & G. Witherby Ltd., UK, 1992.

Willis, Malcolm B. "The Genetics of the Dog" Howell Book House, NYC,
1989 and H. F. & G. Witherby Ltd., UK, 1989.
__________________________________________________ _______________


Eliminating Genetic Diseases in Dogs: A Buyer's Perspective
Copyright 1995 Gary F. Mason. All rights reserved.
Gary F. Mason, .
Reproduced with permission.

Hosted by
K9 WEB