Dog DNA database could help combat dog fighting

A newly formed database of dog DNA is expected to help in legal battles against organized dog fighting.

The database, known as Canine CODIS (Combined DNA Index System), was established by the American Society for the Prevention of Cruelty to Animals (ASPCA), the Humane Society of Missouri and the Louisiana SPCA, and will be maintained at the University of California-Davis School of Veterinary Medicine’s Veterinary Genetics Laboratory (VGL).

The database contains DNA profiles from dogs that were seized during dog fighting investigations as well as profiles from samples collected at suspected dog fighting venues. Most of the DNA in the Canine CODIS was collected during raids on dog fighting operations last year, which netted about 400 samples.

The way the system works is that when a dog is seized from a dog fighting raid, cheek swabs are collected and submitted to the laboratory for DNA testing. Investigating agencies may also submit DNA from unknown sources such as blood drops. The DNA profile is then searched against the Canine CODIS database. If there is a match, or “hit,” the agency submitting the new sample and the agency that submitted the original CODIS sample are given each other’s contact information, said ASPCA Forensic Veterinarian Melinda Merck, DVM.

“From there, it is up to those two investigating agencies to discuss their confidential case information,” Merck said. “They may find ways their cases are linked that may enhance or bolster their investigations. When we did this on the original 400 dogs, we found links between multiple defendants from the different crime scenes – all through the dogs’ DNA.”

Beth Wictum, director of the forensics unit of the Veterinary Genetics Laboratory, said no breed information will be maintained by in the Canine CODIS, in order to allay fears that the information could be used for breed-specific legislation.

“The samples are identified with both the laboratory’s case number and the submitting agency’s identifier,” Wictum said. “A DNA profile using 39 autosomal markers is developed for each individual. This is many more markers than is normally used for individual profiling because we run programs to identify relatedness between the dogs.”

In court, the DNA evidence can be used to link a suspected dogfighter’s dog to the bloodlines of other known fighting dogs in the database, or to a previously unknown sample found at a suspected dog fighting site. Wictum said the VGL has testified in animal cruelty cases before, and the new database should work to strengthen future cases.

“We have done casework in every state in the U.S. as well as Britain, Bermuda and Canada,” Wictum said. “We have testified in many states for cases involving animal cruelty, dog fighting, dog attack, and human-on-human crimes where animal DNA was collected. Because of recent attention towards forensic science as a result of the NAS report [“Strengthening Forensic Science in the United States: A Path Forward”], we may see more admissibility hearings prior to going to trial.”

Veterinarians cannot submit DNA samples to the database directly, Wictum said. If an investigation is launched, the agency involved will collect and submit the evidence. But veterinarians can help in other ways.

“Veterinarians can play a role by urging law enforcement to submit samples from seized fighting dogs, even if those cases aren’t going to trial,” Wictum said. “Their DNA may help to put someone else in jail.”