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Building a Genetic Reference Database for Dog mtDNA Sequences and SNPs

NCJ Number
Date Published
July 2005
68 pages
This project surveyed the largest known sample set of mitochondrial controls (mts) isolated from domestic dogs across the United States, so as to build a genetic reference database for the identification of dogs from hairs obtained at a crime scene.
The mtCR region was analyzed for 552 unrelated domestic dogs. One hundred and four haplotypes were identified, 36 of which had not been previously reported. In addition, 24 new polymorphisms were identified that are not recorded in previously published datasets. The random match probability of the current dataset was 0.041. The study concluded that there was no genetic basis, based on the mtCR sequences, for grouping dogs by purebred or mixed or geographic location within the continental United States. Dogs of the same breed share similarities in their mtCR sequence, even if the sequences are not identical. This indicates that it is necessary to collect multiple individuals from the same breed in order to build a thorough database of mtCR polymorphisms. Also, purebred and mixed-breed individuals can be combined into one database. The same is true for dogs from separate geographic locations. Although the mtCR has proven successful for human forensic evaluations by revealing ethnic origin, domestic dogs of apparently unrelated breeds often for large haplotype groups based on identical control region sequences. In an attempt to break up these large haplogroups, the current study sequenced the remaining approximately 15,484 based pairs of the canine mitochondrial genome for 64 individuals, adding 15 previously published dog mitochondrial genomes to those collected. Phylogenetic and population genetic methods were used to search for additional variability in the form of single nucleotide polymorphisms (SNPs). A total of 356 SNPs and 65 haplotypes were identified by using the mitochondrial genome that excludes the control region. The mtCR was also evaluated for the same 79 dogs. Extensive tables and figures and 26 references

Date Published: July 1, 2005