American Miniature Schnauzer Club,
The AMSC’s Contributions to
Miniature Schnauzer Health Research
Miniature Schnauzers are hardy dogs. Fortunately, they suffer from fewer genetic disorders than do many other breeds. Nonetheless, Miniature Schnauzer breeders have long been in the forefront in supporting research on genetic disorders.
Congenital Cataracts (“cc”)
In the late 1950s, a veterinary student of Dr. Lionel Rubin at the University of Pennsylvania identified a form of congenital cataracts in Miniature Schnauzers. They were initially called congenital juvenile cataracts (“CJC”) but are more accurately called congenital cataracts. The cataracts are present in fetuses and can also be seen with a relatively simple and inexpensive “slit-lamp” examination in very young puppies as soon as the eyes are open. Congenital cataracts are bilateral, i.e., present in both eyes. They can be seen with the naked eye in some dogs as young as 1-2 years of age, but in many cases are not visible to the naked eye until the dog is older. In time, affected animals become blind in both eyes.
The AMSC’s effort to eliminate congenital cataracts began in the 1960s with a series of articles alerting breeders to the problem and providing them with such information as was known. The AMSC and its members then supported research by Dr. Richard Donovan, a veterinary ophthalmologist in Boston, to determine the mode of inheritance of cc in Miniature Schnauzers.
In 1973, once it had been learned that cc were caused by a simple autosomal recessive gene, the AMSC Board adopted a voluntary pledge by AMSC members to have dogs used for breeding, and all puppies, examined by a veterinary ophthalmologist and to retire from breeding any animals affected by cc or who had produced any affected puppies. The AMSC Board then initiated a program to test breed clear-eyed animals to affecteds and thus either establish that the animal being tested was a carrier or establish a probability that the animal being tested was a clear.
As a result of this program, congenital cataracts have become very rare in show stock Miniature Schnauzers in the United States and Canada.
Progressive Retinal Atrophy (“PRA”)
PRA refers to a group of genetic eye disorders in which the retina (the light-sensing tissue at the back of the eye) degenerates, resulting in blindness. PRA is found in more than 70 breeds of dogs, and in many other mammals, including humans. In humans, the diseases are called retinitis pigmentosa. There are several known varieties of PRA, each caused by a different genetic defect. The types vary in the age of onset of symptoms, and in the rate of progression, but the end result is the same in all: blindness. Only one form of PRA is known to occur in Miniature Schnauzers. It is called photoreceptor dysplasia (“pd”). Pd is not known to occur in any other breed of dog.
Just as congenital cataracts were being eliminated, PRA became a more serious problem in the breed. Unfortunately, however, PRA usually does not become apparent in Miniature Schnauzers until an affected animal is about three years old. It was thus not practical to eliminate the disease through test breeding. Only recently, with the development of recombinant DNA technology, has research to find a solution become feasible.
In April 1994, AMSC members learned that Dr. Gustavo Aguirre and his colleagues at the Baker Institute at Cornell University had developed a DNA test for PRA in Irish Setters. Members of the AMSC's PRA Committee began discussing the feasibility of raising funds for research into identifying the mutated gene that causes pd and developing a DNA test to detect it.
At the AMSC Board's October 1994 meeting, the PRA Committee presented a proposal for a 3- year research project and a plan to raise the needed $175,000. With the Board’s approval, the fund raising began. In early 1995, at the AMSC’s request, the American Kennel Club agreed to match funds with the AMSC up to $87,500, that is, up to half the cost of the research. The AMSC then negotiated and drafted a research agreement among the AMSC, the AKC and the Baker Institute.
The research began in February 1996. The Baker Institute appointed Dr. Qi Zhang to work full time on the Miniature Schnauzer PRA research, under Dr. Aguirre’s supervision.
One facet of the research involved determining whether any genes previously identified as linked to retinal development were responsible for causing pd. Dr. Zhang examined 7 candidate genes thought most likely to be the cause of pd. Unfortunately, his work proved that pd was not caused by a mutation in any of those genes. At the same time, Dr. Zhang began working on subtraction analysis - comparing complementary DNA from normal dogs with that from affected dogs. As a result of that work, he identified two genes for further study: the Phosducin gene (which had previously been identified as being retinally-linked) and a previously unknown gene. Since then, Dr. Zhang has worked on cloning the newly discovered gene, a prerequisite for determining whether it is a cause of pd. The work has gone slowly because the newly discovered gene is very large. As of February 2000, the researchers had not yet succeeded in cloning the new gene. Dr. Zhang and Dr. Aguirre believe Phosducin is a likely location of a potential gene defect, but they do not believe that it alone is responsible for pd.
In order to obtain more genetically diverse DNA to use in the subtractive analysis, the researchers cross-bred a pd-affected Schnauzer to a prcd-carrier Poodle and a pd-carrier Schnauzer to an erd-affected Elkhound. Affected offspring resulted from the matings, indicating that pd is not a simple autosomal recessive. (Many past and present members of the AMSC’s PRA Committee had suspected that pd was not a simple autosomal recessive, as earlier research had concluded, because the incidence of PRA in Miniature Schnauzers seemed to be much lower than would be expected if inheritance followed a simple autosomal recessive inheritance pattern.)
The researchers believe that the affected cross-breed offspring indicate either:
a. that there are several (2 or 3) different types of PRA in Miniature Schnauzers, caused by separate autosomal recessive disorders, including prcd (the form of PRA found in Poodles, Labrador Retrievers and Cocker Spaniels), erd (the form of PRA found in Norwegian Elkhounds), and pd, or
b. that pd is caused by a combination of two or more genes.
The AMSC/AKC funding of the research at Cornell ended December 31, 1998. The research is continuing with funding from the Foundation Fighting Blindness.
The Wide Support of the PRA Research
Miniature Schnauzer breeders, exhibitors, and clubs in three countries (the U.S., Canada, and Australia) have generously supported the research. So have several all-breed clubs and the AKC. Contributions have been received from more than 300 donors. The AMSC thanks all of them for their generous support, including the following clubs:
· Metropolitan Cleveland Miniature Schnauzer Club
· Paul Revere Miniature Schnauzer Club
· Miniature Schnauzer Club of Canada
· Miniature Schnauzer Club of Northern California
· Twin Cities Miniature Schnauzer Club
· NorCal Breeders Association
· Miniature Schnauzer Club of Michigan
· Miniature Schnauzer Club of Southern California
· Greater Columbus Miniature Schnauzer Club
· Greater Cincinnati Miniature Schnauzer Club
· British Columbia Miniature Schnauzer Club (Canada)
· Sir Francis Drake Kennel Club
· Harrisburg Kennel Club
· Chicago Miniature Schnauzer Club
· International Kennel Club
· Portland Miniature Schnauzer Club
· Miniature Schnauzer Club of Atlanta
· Lone Star Miniature Schnauzer Club
· Hawkeye Miniature Schnauzer Club
· Schnauzer Club of New South Wales (Australia)
· National Capital Region Miniature Schnauzer Club (Canada)
· Cactus State Miniature Schnauzer Club
· Centennial State Miniature Schnauzer Club
· Penn Ohio Miniature Schnauzer Club
· Sturgis Kennel Club
· Milshore Miniature Schnauzer Club
· Florida West Coast Miniature Schnauzer Club
· Mount Vernon Miniature Schnauzer Club
· Kennel Club of Niagara Falls
· Schnauzer Club of Victoria (Australia)
· Idaho Capital City Kennel Club
· Chenango Kennel Club (New York State)
· Gateway Miniature Schnauzer Club
Congenital Portal Systemic Vascular Anomalies (“Liver Shunts”)
The AKC Canine Health Foundation approved a funding proposal of $14,500 for an investigation of oxidant stress and antioxidant levels in livers of dogs having congenital liver shunts. In 1998, the AMSC agreed to join the Foundation and other breed clubs in funding the research.
Liver shunts are extra blood vessels that allow a portion of the animal’s blood to bypass the liver. At present, the definitive treatment for large shunts is surgical removal. Unfortunately, efforts at complete removal are often unsuccessful. Dogs with untreated liver shunts often develop progressive liver disease, resulting in liver failure. The proposed research is aimed at comparing (1) oxidative damage, (2) bile acid profiles, and (3) the level of antioxidants (such as Vitamin E) in normal dogs with those in dogs with shunts. If the research identifies decreased liver antioxidant levels in dogs with shunts, the researchers would then propose further studies to determine the benefit of feeding antioxidants to dogs with shunts.
The AMSC’s Partnership With the AKC Canine Health Foundation
The AMSC began working closely with the AKC Canine Health Foundation, upon its organization in late 1994. The AKC told the AMSC that the AMSC-sponsored PRA research was the first occasion on which the AKC entered into a matching funds program with a breed club. Virtually all of the Foundation’s grants now involve matching funds from various breed clubs. Similarly, it was the AMSC that first proposed that the Foundation offer breed-specific accounts within the Foundation; and the AMSC was the first to open a breed-specific account.
The AMSC is proud of its leadership role in working with the Foundation to develop the Parent Club Partnership Program. It plans to continue working with the Foundation to identify proposals for research in areas of concern to Miniature Schnauzer breeders and to coordinate joint funding agreements with other parent breed clubs for research of joint interest. Handouts for the Foundation’s 1999 National Parent Club Canine Health Conference held in St. Louis in October 1999 featured an article on the AMSC’s experience in raising funds for the PRA research at Cornell.
The AMSC’s criteria for selecting research to support are (1) a health problem of significant concern to Miniature Schnauzer breeders, (2) a proposal well-designed to attack the problem, and (3) a reasonable probability of a successful outcome within an affordable budget.
Our efforts so far are just a beginning. Contributions from Miniature Schnauzer owners are needed to continue research into health problems of Miniature Schnauzers. Please make checks payable to the AKC Canine Health Foundation and mark Miniature Schnauzer Fund in the memo section of the check. Please mail the checks to the Chair of the AMSC Fund-Raising Committee:
7607 Whitegate Avenue
Riverside, CA 92506-5441
Contributions are tax deductible for U.S. citizens and residents as charitable contributions.
We have received many gifts in memory of a friend or of a Miniature Schnauzer who has passed on. We have received other gifts in honor of new championships and significant wins. On request, we will send a beautiful acknowledgment card (designed by Lori Bush) to the person being honored or the next of kin of the deceased. We also encourage Miniature Schnauzer owners to leave gifts to the Miniature Schnauzer Fund in their wills so as to leave a living legacy to help the breed we love. Please be sure to specify the name of the Fund in full, so that it will be clear to your executor where you want the gift to go:
“Miniature Schnauzer Fund of the American Kennel Club Canine Health Foundation.”
Last revised: November 30, 2001
Copyright 1996, 1997, 1999, 2000. American Miniature Schnauzer Club, Inc. All rights reserved.