April 16, 2009

Study: Red pandas have a sweet tooth

U.S. scientists say they've determined the red panda is the first non-primate mammal to display a liking for the artificial sweetener aspartame.

Monell Chemical Senses Center researchers in Philadelphia said the unexpected affinity for an artificial sweetener might reflect structural variation in the red panda's sweet-taste receptor and the findings might shed light on how taste preferences and diet choice are shaped by molecular differences in taste receptors.

Greater insight into why we like artificial sweeteners could eventually lead to the development of more acceptable sugar substitutes, potentially benefiting diabetics and other individuals on sugar-restricted diets, said the study's senior author, Joseph Brand, a Monell biophysicist.

Many species like sweet-tasting foods, but there are some exceptions. In an earlier study, Brand and Monell comparative geneticist Xia Li reported that cats -- both domesticated and wild -- cannot taste sweets due to a defect in one of the genes that codes for the sweet-taste receptor.

The current research extended those findings by relating sweet preferences to genetic analyses of sweet-receptor structure in six related species -- red panda, ferret, genet, meerkat, mongoose, and lion.

The study is detailed in the Journal of Heredity.