DNA Fatigue

Why keep giving?

by C.A. Sharp

Rev. May 2013

 

Hurricanes, tsunamis, earthquakes—the devastating series of major disasters in the recent past spurred world-wide calls for donations to relief organizations.   As time went by and more crises occurred, relief organizations worried that “donor fatigue” would hinder their ability to respond.  There is only so much people are willing, or able, to give.

While difficulties generated by canine genetic issues have little impact on the world at large, the scientific and technological explosion in the field of genetics may be producing its own variety of donor fatigue.  These advances provide great benefit to dogs, so their owners and breeders are recipients of a barrage of requests for canine DNA samples.  Major registries offer DNA parentage verification services that, in some instances, require DNA to be submitted before registration can proceed.  A growing number of research projects actively seek donations of DNA samples through messages to canine chat lists and advertising or notices in dog-oriented magazines and newsletters.  Some researchers set up DNA collection clinics at canine events.

One canine geneticist recently lamented that, where once he had found breeders and owners not only willing but anxious to supply samples, more recently he met rebuffs.  Some people told him they had “already donated.”  How much DNA donating is too much?  And how often should we be expected to provide samples?

Understanding what you are donating for, the type of sample you are providing, and who it is going to is important.  All may have a bearing on whether you do—or don’t—wish to give and whether a previous donation may apply to the current request.

Dog owners sometimes ask if the DNA they sent to a registry’s DNA program can be used by a researcher who is investigating a breed health issue.  The purpose of the registry-operated programs is to establish positive identification for individual dogs and verifying parentage.   These programs help maintain studbook integrity for the registry and give owners and breeders a vehicle by which a dog can be positively identified and its parentage assured.  The sample is sent to a commercial lab that determines the DNA markers for that dog and issues a report for the registry and the owner.  Samples, and even test results, cannot, in most cases, be utilized by other registries.  In the United States, both the American Kennel Club and the United Kennel Club have DNA programs.  They use the same lab to process the samples.  UKC will accept AKC results, but the reverse is not true.  For Australian Shepherds, accepted for registration by both UKC and AKC, there is also a third DNA program administered by the Australian Shepherd Club of America.  Those results are not accepted by either UKC or AKC.  ASCA cannot utilize the results of the all-breed registries’ programs because ASCA’s program uses a different marker set, tailored specifically to Aussies.

Programs in other countries may or may not use the same marker sets and the registries may or may not accept results from US registry programs.  If you are importing or exporting a dog and either DNA-ID or parentage verification on the dog will be necessary, you will need to check to see what might be required and whether results from the country of origin are acceptable to the registry in the receiving country.

Samples sent to registry programs generally will not be used for any other purpose.  Depending on the sample type, they may be too small to be helpful in a research context even if transfer were available.  In general, you should consider DNA samples submitted to a registry program to be for that purpose only.

DNA samples for research are usually submitted by the owner directly to the researcher.  Usually these samples will be used only for that particular project or other projects done by the same investigator or at the same institution.  Only occasionally will samples be forwarded from one institution to another unless they are cooperating on the same project.  Most research institutions are not maintaining DNA “banks” openly available to the entire research community.  When you give a DNA sample on your dog, you should be sure you understand what the sample will be used for and whether it will be retained for future use.  You should be able to find that information in the project’s literature or on its website.  If not, you should ask.

When you give a sample to research, the type of sample has a bearing on whether any of it might be available for further projects.  The most typical sample types are whole blood and buccal (cheek) swabs.  For the most part, buccal swabs contain only enough DNA for the project at hand and do not store well.  The University of California-Davis has been successful at extending the use of this type of sample, but thus far most other institutions have not.  Blood samples are preferred if multiple uses or long-term storage are anticipated.  However, researchers realize that it is easier to get samples if swabs are an option, since they don’t require a vet visit or special shipping.

Occasionally other types of samples, like tissue taken during surgery or necropsy, might be accepted for a research project.  However, you need to verify that the study can accept them, then make timely arrangements for the proper preservation and shipment of these atypical samples.  Tissue samples your vet sends to a pathology lab may or may not be stored after testing and should not be assumed to be available for transfer to researchers unless prior arrangements have been made.

DNA sent to commercial labs for any of the various DNA tests for diseases or coat color are very unlikely to be made available for any other use.  Most such labs have a working relationship with the research institutions that did the basic research leading to the tests they offer.  They may share a particularly interesting sample with that institution, but this would not be standard practice for all samples received, nor will they make samples openly available for other purposes.  These tests frequently use buccal swabs for test samples, limiting additional-purpose use.  The DNA samples sent to commercial labs should never be looked on as a repository for future use unless the lab has specifically stated they will be retained for such purposes.

In general, every DNA sample you submit on a dog should be assumed to be for one-time use unless you have been specifically informed otherwise.  When new research projects start up or new tests are developed, expect to give new samples.

Research projects are largely dependent on voluntary submissions of DNA samples and data by dog owners.  If you adopt an “I already gave” attitude, you might stifle research vital to your dogs’ health and wellbeing.  It is vital that breeders and owners continue to provide appropriate samples to pertinent research efforts.

“Appropriate” samples are those that fit the protocols of the particular study.  If you offer a sample from your dog and it is turned down because it doesn’t meet the criteria for the project, don’t take it personally.  The researchers simply want to get the samples most likely to help them reach their research goal.  Samples from dogs diagnosed with whatever disease is under study are always welcome, though some studies are limited to one or a few breeds or the dogs sampled may need to meet particular diagnostic criteria to fit the study.  Sometimes relatives of affected dogs are wanted.  The most current techniques require a set of unrelated,  healthy “controls” to compare to the affected dogs.  In most cases, the affected dog needs to be part of the study before samples of healthy relatives are wanted.  The definition of “relative” will vary from one study to another.  You need to make sure your dog meets the researchers’ needs.  Sending unsuitable samples is a waste of time and expense for the researchers.

If, for any reason, you are unhappy with a particular researcher, don’t refuse to support research in general.  Researchers are every bit as individual as dog people.   Your feelings about one individual or research group shouldn’t extend to the entire profession.

Research takes time and not every project will be successful.  The failure of a particular effort to produce short term results—or any results at all—does not necessarily mean the researchers weren’t doing their jobs.  The samples you send to their next project may be the ones that give you the answers you need.

If you’ve been in dogs for a long time, you’ve probably felt the disappointment of not being able to assist a research project that comes along after you lose a dog to  the disease, putting a potentially valuable sample beyond reach.  DNA banks are an attempt to overcome that problem.  This type of “bank” is a collection of DNA samples linked to pedigree and health data.  Some research institutions maintain reference sample collections for one or more breeds.  Some laboratories offer sample storage programs to breed groups, generally for a fee which may require periodic renewal.  Most of these programs are limited to one or a few breeds.  Samples may or may not be accessible to the donor after submission, making them unavailable for screening tests developed after the dog is gone.  If you submit a sample to one of these programs, be sure you are familiar with the scope of the program, who has access to portions of the samples, and under what conditions.

The program that may offer the greatest potential for long-term storage of a comprehensive set of purebred dog samples is operated by the Canine Health Information Center (CHIC.)  After a trial program with the cooperation of the Golden Retriever Club of America, the CHIC DNA Repository was opened to all CHIC breeds in April of 2006.  Over 150 breeds are participating in CHIC, which was established by the Orthopedic Foundation for Animals and the AKC Canine Health Foundation to promote the open exchange of health information.  The contact networks of these two organizations in the canine research community make CHIC ideally situated for providing a high-profile, widely accessible DNA storage facility.

CHIC’s DNA Repository accepts both blood and buccal swab samples.  Blood is processed and stored by the Animal Molecular Genetics Laboratory at the University of Missouri.  The Veterinary Genetics Laboratory at the University of California-Davis maintains the cheek swab collection.   Find information by clicking here.

Your dog has plenty of DNA to spare, even after you’ve submitted to registry programs and had breed-appropriate DNA screening tests done.  When you become aware of a research project to which your dog might contribute, send in a sample.  Buccal swabs are easy and generally aren’t going to cost you more than the postage to mail them back.  Even blood samples aren’t that difficult, though the shipping requires more care.  Vets often waive fees if they know the draw is for research, especially if it doesn’t require a special appointment.  If a clinic is available at a show or other event, make use of it.  And remember the importance of setting aside for the future and get samples from your dogs into a DNA bank.

Most importantly, never tell a researcher, “I already gave.”  The sample you refuse may hold the key to solving a serious breed health issue.