UC Davis School of Veterinary Medicine Veterinary Genetics Laboratory

Genetic Diversity Testing for Bulldogs (English Bulldogs)

(Phase 1 - Research)


The Veterinary Genetics Laboratory has an active collaboration with Dr. Niels C. Pedersen in studying genetic diversity in pure breeds of dogs. Dr. Pedersen has been actively researching the relationships between lack of genetic diversity, imbalances in genetic diversity within a breed, and increased homozygosity throughout the genome and how it relates to health problems in a breed. He has been especially concerned about the Bulldog because of its significant health problems that appear to be growing worse as individual dogs deviate more and more from the original phenotype of 150 years ago. He has completed a genetic assessment of 139 Bulldogs, mainly from the USA, and has concluded based on this population studied that the breed seriously lacks genetic diversity and that it is approaching the point, if not already reached, where an older and more healthy phenotype cannot be restored by "reverse genetics" using dogs from within the existing population. He is aware that there still is a range of phenotypic diversity still existing in the breed and that there are some dogs that breathe, move, and reproduce much more freely than others. The VGL is therefore interested in testing DNA from bulldogs from other regions of the world and from registered Bulldogs that enjoy much better health. We feel that this information will be essential if breeders decide to use existing genetic diversity to improve breed health. You are therefore welcome to participate in a phase 1 study. Genetic diversity found in these additional dogs will be added to the diversity already identified in the 139 dogs reported.

The Veterinary Genetics Laboratory (VGL), in collaboration with Dr. Niels C. Pedersen and staff, has developed a panel of short tandem repeat (STR) markers that will determine genetic diversity across the genome and in the Dog Leukocyte Antigen (DLA) class I and II regions. This test panel will be useful to Bulldog breeders who wish to track and increase genetic diversity of their breed as a long term goal.

Genetic testing of Bulldogs is now in the development phase -please see Enrolling a Breed During this phase, we need to test 100 or more Bulldogs to provide baseline genetic data necessary to provide breeders with an accurate preliminary assessment of genetic diversity in their breed. We encourage breeders to submit samples from active dogs to further build the database. The goal is to test enough dogs so that no new alleles or DLA haplotypes are recognized.

Price: $50. This is the cost for the dogs that will be tested in the research phase. Once the research phase is complete, the test will be offered at the regular rate of $80.

Results will be reported when sufficient data has been compiled.

Results reported as:
Short tandem repeat (STR) loci: A total of 33 STR loci from across the genome were used to gauge genetic diversity within an individual and across the breed. The alleles inherited from each parent are displayed graphically to highlight heterozygosity, and breed-wide allele frequency is provided.

DLA haplotypes: STR loci linked to the DLA class I and II genes were used to identify genetic differences in regions regulating immune responses and self/non-self recognition. Problems with self/non-self recognition, along with non-genetic factors in the environment, are responsible for autoimmune disease.

Internal Relatedness: The IR value is a measure of genetic diversity within an individual that takes into consideration both heterozygosity of alleles at each STR loci and their relative frequency in the population. Therefore, IR values heterozygosity over homozygosity and uncommon alleles over common alleles. IR values are unique to each dog and cannot be compared between dogs. Two dogs may have identical IR values but with very different genetic makeups.

Veterinary Genetics Laboratory, Tel 530-752-2211, Email VGL