In the near future, cat owners may be shopping with a greater purpose: selecting commercial foods that nutritionally harmonize with their pets' genetic makeup — maximizing their health — and longevity.

The reason: an emerging field of science called nutrigenomics.

A glimpse into such a future came recently at an international conference in London, where leading geneticists, nutritionists, veterinarians, and scientists presented their findings about the benefits of nutrigenomics for companion animals.

Nutrition is a key to a kitten's health. This photo shows two littermates, one much smaller than the other as they share a food bowl together.

It provides a molecular understanding as to how common dietary substances influence the health of a cat — or person's — genetic makeup. In essence, this nutrient-gene interplay can "turn on" good genes and "turn off" harmful ones.

"The science of nutrigenomics gives us great insight into understanding how and why certain breeds are predisposed to particular conditions," says John Innes, BVSc, PhD, professor of small animal surgery at the University of Liverpool, England. "This gives us one more tool in our ongoing quest to treat and prevent illness."

Rebecca Remillard, DVM, a board-certified veterinary nutritionist at Angell Animal Medical Center in Boston and on the Catnip advisory board, concurs.

"I've not been directly involved in nutrigenomics research, but I can say that it holds out a hope for some diseases that nutrition, at best, manages and often, manages poorly," says Dr. Remillard. "The first time I saw reports about nutrition and gene expression was in 1993. I suspect that we will come up with better answers to treat a host of diseases due to continued research into gene expression."

Jerold Bell, DVM, clinical associate professor in the Department of Clinical Sciences at Cummings School of Veterinary Medicine at Tufts University, embraces what nutrigenomics can provide to the health of companion animals.

"Nutritionists and geneticists have been working together especially at pet food companies, on the relationship between nutrition and genes," says Dr. Bell, a geneticist who serves as director of the Canine and Feline Breeding and Genetics Conference hosted by Tufts from September 30 through October 1.

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Food is fuel as this energetic cat demonstrates with a full-body stretch. Researchers are studying how nutrition and a cat's genetic makeup can influence his health.

Both Dr. Remillard and Dr. Bell envision the day that geneticists and nutritionists can identify genes that cause certain breeds to be prone to such health conditions as kidney stones, epilepsy, and diabetes. Once identified, these genes could essentially be "turned off" through providing specific nutrients in the diet.

Utilizing the theory of nutrigenomics with clinical studies, Hill's Pet Nutrition recently unveiled Prescription Diet Canine j/d for dogs with arthritis and joint problems. Researchers spent more than a decade and conducted clinical trials with more than 50 practicing veterinarians involving more than 500 dogs.

Their finding led them to include a specific omega-3 fatty acid called eicosapentaenoic acid (EPA) in the new j/d product. EPA's high concentrations of fish oil have been shown to "turn off" a degenerative enzyme that causes cartilage degradation. Studies indicated that about one in five adult dogs suffer from arthritis, making it the seventh most common ailment reported to veterinarians worldwide.

Of the tested dogs, 82 percent were able to walk without limping, and demonstrate increased range of motion after one month of being put on the j/d diet. Of those dogs who needed non-steroidal medications, dosages were able to be decreased by 25 percent, reports Debra Nichol, PhD, vice president of product development for Hill's Pet Nutrition.

Although j/d is the first gene-linked diet and requires a veterinary prescription — experts in the nutrigenomics field and veterinary nutrition predict many more such DNA-influenced pet foods will be showing tip on store shelves for dogs as well as cats. Genetic engineering is only in its infancy on the impact it can make on the health of dogs, cats, and people.


CANINE RESEARCH LEADS THE WAY
Canine research in this area is about 10 years ahead of feline research, due to the formation of the Canine Health Foundation established by the American Kennel Club, notes Dr. Bell. He said this foundation funds millions of dollars for genetic research annually.

"The cat fancy people and feline researchers started later than the dog world, but the quantity of research in this field will certainly help them catch up," says Dr. Bell.

This "gene silencing" or "gene speaking" form of science is being actively pursued by researchers to benefit people. One recent study published in the journal Nature Chemical Biology, described how scientists were able to efficiently shut down the expression of genes by turning them on or off at the DNA level. This study shows that chromosomal DNA is accessible to and can be controlled by synthetic and natural molecules.


LEARNING TO TURN ON, OFF GENES
"With this information, one could easily turn on or off gene expression, as well as think about ways to correct genetic disease by changing mutant gene sequences back to normal," says David Corey, PhD, professor of pharmacology and biochemistry and one of the study's authors. "Virtually every disease starts at the level of malfunctioning gene expression, or viral or bacterial gene expression. This is an approach that could theoretically produce a drug for the treatment or cure of almost any disease."

In summary, experts predict a very healthy future for people and pets.

"We are only beginning to learn how certain foods can manipulate the genes we are born with," says Robert Pickard, PhD, director of the British Nutrition Foundation. "We know the 'addresses' of genes. Now, we need to learn their 'occupations' and what influence certain foods have on modifying these genes."