Genetic Counseling

A Discipline in Gestation

by C.A. Sharp

First published in Double Helix Network News, Winter 2007,  Rev. May 2013

 

It started with an e-mail, but could as easily have been a phone call or letter.  Upon occasion, it takes place face-to-face.  The writer told me his dog had been diagnosed with an inherited disease.  He wanted to know what this meant not only for that dog, but for related dogs in his kennel and that those he’d sold to other people.  He gives me his name, Kevin, and that of his dog, though not everyone who contacts me is comfortable providing this information. Even if they don’t, I’ll do what I can to help them.

I’m not a vet, so I didn’t offer Kevin treatment advice for his dog.  I did ask how the dog was diagnosed and what testing had been done.  The disease is one that can be misdiagnosed.  It also can be difficult to treat.  I suggested he seek a second opinion from a specialist.  Kevin was unfamiliar with the disease, so I gave him some basic information about it.  I also told him it is genetic and how it is inherited.

I discussed the breeding implications for the dog and its kin.  Since Kevin volunteered detailed information, including his dog’s pedigree and relationship to his other dogs, I was able to tailor my response to his specific situation.  Since there is a DNA test for this disease, I told him what it is, how to have it done and which dogs he should get tested.   I explained what type of results he might receive, what they would mean and how to apply them to his breeding decisions.  I suggest that after he has the test results, he get back in touch with me so we can discuss them in detail.

Kevin and many others like him have come to me because I have a high level of knowledge of canine genetics and hereditary disease.  I am particularly knowledgeable about my own breed, the Australian Shepherd.  Like Kevin, most people who contact me have Aussies.  If you asked them why they consulted me, they’d say they wanted help or advice.  What I have provided for them is genetic counseling.

Genetic counseling for humans has been an established discipline for many years.  For dogs and other animals the practice is in its infancy and, for the most part, has yet to attain professional status or structure.  Dog owners’ need for effective genetic counseling is growing along with the ever-expanding knowledge about the canine genome.

Current sources of information about genetic issues in dogs are largely informal.  A breeder with a problem often seeks advice of other breeders.  An owner might ask her veterinarian.  Club members may ask questions of their breed club’s health committee.  The motivated will embark on a self-education process, using libraries, the Internet and, where available, classes and seminars.  For the most part, these sources will not be able provide advice tailored to the person’s specific situation.  Sometimes what the concerned dog owner acquires is misinformation that helps neither her nor her dog.

Self-education can be helpful, but without someone knowledgeable to mentor the process, the do-it-yourself student may find it difficult to determine which sources are the most up-to-date and accurate.  Some apparent information sources may be aimed more at emptying your pocketbook than providing something that will actually help your dog.

The most frequently contacted sources of advice are probably breeders.  The quality of advice gained in this fashion can vary tremendously, depending on the knowledge level and of the person being asked.  While the insight of an experienced and knowledgeable breeder can be invaluable, not every breeder has attained that level of expertise and some, unfortunately, offer feedback colored by their personal attitude toward the dogs or persons involved.

It isn’t unusual for a troubled breeder to seek advice from several people, leaving her with two or more conflicting opinions.  If any of the advisors are personally vested in the dog under discussion, their emotional reactions can color their response.  This can leave the breeder with more questions than answers, not to mention an emotional burden that only exacerbates her situation.

When a dog is diagnosed with a disease, the vet may offer breeding advice.  However, unless the vet is particularly knowledgeable about not only genetics of that particular disease as well as its frequency in the dog’s breed, the advice may amount no more than a warning against breeding the dog and, often, its relatives.

This does not imply that veterinarians aren’t doing their job.  Their specialty is the diagnosis and treatment of disease and injury.  They treat multiple species.  In dogs alone there are over 400 identified genetic diseases and a similar number of different breeds.  Though a few vets specialize in genetic disease, for most of them genetics is secondary information that often does not play a large role in their practice.  Human doctors, who deal with only one species, also generally do not to have a strong background in genetics.  That is why genetic counseling exists as a separate, but complementary, discipline in the human medical field.

The science of genetics has been growing exponentially in recent years.  The sequencing of the canine genome has lead to rapid advances in the identification not only of disease genes, but those associated with traits like coat color.  All this research is leading to the development of a growing number of genetic screening tests.   The abundance of new information can be overwhelming and the need for advice tailored to specific breeders’ concerns is growing.

Breeders need to know what genetic diseases and inherited faults they are likely to encounter in their breeds and how they are inherited.  If there are screening tests, they need to know when and how those tests should be used.  They also need to know what they can do to minimize the risk of things going awry in dogs of their breeding.  The need for canine genetic counseling services provided by qualified individuals is obvious.

Human genetic counselors get their clients by referral from doctors or other medical professionals.  Their advice is most frequently offered to individuals or couples who are concerned about future children.  More recently they have also counseled individuals about DNA tests they may have had or are considering.  Generally, only one disease is at issue.  The counselor will explain how that disease is inherited.  If screening tests are available, they may or may not have been done when the counselor first sees the clients.  If the clients have not been tested she will explain what the tests are and what they can reveal, leaving the decision to test or not to the clients.  If tests have been performed, she will interpret the results and explain what level of risk the clients might have for themselves or for giving birth to an affected offspring.  Human genetic counselors will have access to the medical documentation pertinent to the case.

The canine genetic counselor may or may not be presented with documentation.  If the person seeking counsel has learned that his dog’s sire has produced a genetic problem, he may not have direct access to records or the treating veterinarian.  The counselor must then make it clear that the advice given is based on the information as provided by the client.  (“If your dog’s brother has hereditary cataracts, then … )

If the client is the owner of the affected dog, the counselor needs to determine whether the client’s understanding of the situation is accurate.  Educating the client or suggesting further consultation with treating vets or specialists may be necessary before any breeding advice can be given.

Because human genetic counselors are dealing with questions surrounding human reproduction, they do not tell clients that they should or should not have offspring.  They enable their clients to make an informed decision for themselves.  The situation with purebred dogs is somewhat different; dogs’ reproductive lives are very much under human control.  While the ultimate decision of whether or not and how to breed remains with the breeder, it is my personal feeling that the canine genetic counselor would be remiss not to offer an informed opinion on whether or not to breed a particular dog under the circumstances presented.  The counselor should let the client know what precautions should be considered in mate selection should he decide to breed the dog.

Even canine reproductive choices can be fraught with emotion.  It is vital that anyone offering canine genetic counseling services remain objective and non-judgmental, remembering the ultimate decision belongs to the owner of the dog.  One test of the counselor’s objectivity unlikely to be encountered by those in human practice, is the possibility of having more than one client seek advice about the same situation.   This has happened to me more than once.  Ideally, the counselor should refer the second client to someone else.  Unfortunately, there often isn’t another person to refer to who has the necessary combination of disease and breed-specific knowledge.  In addition, even admitting that “someone else” has already requested services can lead to a breech of confidence and possible repercussions toward the counselor or between the clients.

Since there are no formal guidelines for me to fall back on, my practice has been to treat parties that are openly cooperating with each other as a group once I have asked each, in turn, if they are willing to participate in a joint discussion.  In other cases I’ve had two or more people contact me about the same circumstance with markedly different sets of “facts.”  In such an instance I may or may not know what the actual case is.  Even if I have an opinions about which person is playing straight, I take each client at face value.  I base my responses on the assumption that what the she has told me is accurate.  I also go to great lengths to make sure no one is aware of other contacts about the case.

Another challenge faced by canine genetic counselors is the vast array of breeds, each representing a distinct population.  I suspect that most people offering counseling today are, like me, single-breed specialists.   If someone is to adequately serve people with different breeds of dog, the advice must be appropriate for the breed.

Advice that is accurate for a Standard Poodle owner might differ from that given to someone with Mastiffs.  The genetics of a particular disease may differ between the breeds, so an approach that could help with one might be unhelpful or even detrimental for the other.  The frequency of the disease in the breed under discussion is also important.  The breeding advice one might give for a rare problem can differ from that for dealing with a common disease.

While I am periodically contacted by people in other breeds, I make sure they are aware up front that I am not a specialist in their breed and can only offer general advice based on my own experience and what I am able to glean from reference works, which I cite so they can follow up themselves if they wish.

At this point in time there are no formal ethical or professional standards for genetic counseling on canine issues.  As time goes by, the need for these services will grow.   When the demand is sufficient, formal training programs should be established. Professional organizations will need to form, with the responsibility for developing and maintaining standards of performance and ethics.  Once genetic counseling for canines and other animals becomes accepted, cooperative referral networks can be developed with the veterinary profession.  Our dogs’ health will be the better for it.

In the meantime, I and others like me will continue to study and keep up-to-date on research so we can share that knowledge and, most importantly, the application of the knowledge to dog breeding with Kevin and his fellow breeders for the benefit of their dogs.