Pet DNA analysis to yield swifter disease detection

Experts suggest pet DNA samples soon will supply veterinarians with diagnostic tools to predict which animals are the most likely candidates to carry myriad diseases.

"Technology is advancing fast enough that, within 10 years, DNAanalysis for disease resistance for everything you can imagine will becomepart of every progressive, veterinary practice in the country, both smallanimal and large," says Dr. Brad Fenwick, a veterinarian at KansasState University, where his laboratory operates a DNA registry for dogs.

The laboratory, funded by the National Greyhound Association, is largelyrecognized as "bulletproof" evidence in forensics cases. It alsoexists, in part, to serve as a genetic analysis tool for research into doghealth improvement in general.

DNA analysis can be at least as precise in pets as it is in humans andcan have a powerful impact in a courtroom, according to Dr. Joy Halverson,a veterinarian and geneticist at the University of California, Davis. Halversonhas already analyzed animal DNA for prosecutors in several cases involvingdogs.

Canine-specific DNA advances in the courtroom are triggering equal investigationsinto feline DNA projects, both forensically and medically speaking.

Felines not forgotten

A feline-oriented DNA database is well under way as a collaborative effortof the National Cancer Institute, a research arm of the National Institutesof Health, which is funding the project, and the U.S. Department of Justice,which intends to dedicate the project to forensics casework.

Researchers at NCI say the database of feline DNA can match samples,for forensic purposes primarily, with an accuracy of more than 100 millionto one.

A prominent figure in feline DNA research and the genetic database, MarilynMenotti-Raymond, Ph.D., of NCI, says the DNA sample collection, which numbersmore than 1,200 samples from 38 cat breeds, is near completion.

The plan, according to Raymond, is to turn the database over to the JusticeDepartment, once the genetic markers are completed. Genetic markers representsegments of DNA. Each exhibits variability in a population of dogs, catsor other animals.

"If you use enough genetic markers, then each individual would haveits own unique genetic profile," Raymond tells DVM Newsmagazine.

"We're developing this as a forensic typing system in the cat,"she says. "It can be used for genetic individualization of cat specimensthat are found at crime scenes."

Once the database work is finalized, experts expect the number of casesinvolving DNA to spike notably.

The Justice Department failed to return calls seeking comment.

Bigger picture

Raymond adds that, although the NCI/Justice Department feline DNA databaseis primarily intended to yield convincing forensic evidence, there is asecondary purpose. The database and its genetic markers are a notable offshootof a larger initiative known as the Feline Genome Project.

"The purpose of the markers (in the database) is they're part of(what) we're using in developing the genetic map of the cat," saysRaymond.

The genetic markers can dually help scientists identify genes associatedwith inherited and infectious pathology in the cat, while also serving asevidence for forensics cases.

"We're using the cat as a model for human hereditary disease andinfectious disease," Raymond adds. "It's the best animal model,really, for AIDS, with the feline version of AIDS."

Why DVMs should care

Forensics casework aside, should DVMs care about DNA casework?

"Of course," Halverson tells DVM Newsmagazine. Veterinarians,although seldom involved at this point, do have a crucial role in DNA applications.

"To the extent that veterinarians work with cat and dog breeders,I can see DNA (analysis) impacting them," she says.

"One, they may end up taking samples to send to these various databanks. Second, they may end up answering a lot of questions, because thelay public will know what's going on as much as anybody else."

From a practical standpoint, Raymond says she suspects veterinarianswould have more use for the genetic map of the cat than the database.

"They could be using the markers (of the Feline Genome Project)diagnostically, just like they can in human populations to say you're acarrier of cystic fibrosis. They'll be able to tell the pet owner, yourcat is a carrier of polycystic kidney disease," says Raymond.