For at least 50 years scientists have known that cats are indifferent to sweets. Now, thanks to new research from scientists at the Monell Chemical Senses Center, there is a molecular reason for the phenomenon. In a nutshell, in cats the gene that would normally allow them to taste sweets is defective, it is not transcribed, said Joseph Brand, PhD, associate director at Monell and co-author of the study, which was published in the inaugural issue of PLoS Genetics, a free peer-reviewed journal.

Three years ago Brand began his research with colleague Xia Li, PhD, using purchased feline DNA to identify the chromosome sequences that comprise the sweet receptor. Brand will continue to work with the cat’s other taste receptors to understand how the taste system drives dietary choice, he said. “Taste is the fundamental sense in determining personal dietary choice,” he said and added, “Taste receptors provide us with a tool to evaluate taste stimuli.”  The Monell scientists expect to publish additional research on taste in the next year.

For practical purposes, the research may help nutritionists create a prescription food that would be palatable to sick cats, animals that may otherwise starve themselves to death. In addition, the research may be helpful in alerting owners to the dangers of giving their cats sweet treats. “Many sweet things are harmful to cats,” Brand said. “For millions of years, cats have not eaten simple carbohydrates and they may have lost their ability to metabolize them,” he explained, and added, “For example, most cats cannot break down sucrose.”