This report presents the methodology and findings of a project that developed and validated a canine forensic fluorescent-based multiplex composed of 18 independently segregating STR (short tandem repeat) markers that are robust, reliable, and informative for all dog breeds.
Each pedigreed dog population was found to be genetically distinct and could be differentiated from the mixed-breed dog population. Genetic diversity was slightly clinically distributed among the different U.S. regions. In addition to STR markers, the panel also includes the gender identification and the canine Zinc Finger gene. The results provide further support for using allele frequency data with the canine STR multiplex in order to indicate the significance of identity testing for forensic casework, parentage testing, and breed assignments. The multiplex was used to profile Pit Bull Terrier and Rottweiler samples (2 breeds often involved in forensic cases); mixed-breed samples; and a collection of pedigreed pure-bred dogs (over 667 unrelated individuals representing over 50 breeds recognized by the American Kennel Club). These subpopulations formed the foundation of the developed canine database. The resulting data were used to assess genetic and geographic substructure, as well as to estimate recombination ratios and inbreeding coefficients. In addition, genetic diversity among and within the regional and breed datasets were compared. This project addresses recent court challenges of canine DNA analysis that have demonstrated the need for a standardized canine STR panel that has been validated according to human forensic guidelines. Detailed descriptions of the methods used address the population genetics study and genotype database development, development validation studies, and nomenclature development. 5 tables, 4 figures, 76 references, and a listing of 21 publications that have disseminated the research findings
Date Published: July 1, 2005