Some strains are less sensitive to sweet taste than others, and scientists had found the approximate location of the responsible gene on a mouse chromosome. During their work, scientists surveyed that region of the mouse chromosome and the corresponding region of human DNA, where they eventually identified a gene that looked like it could give rise to a taste receptor. Margolskee's group proposed how the version in insensitive mice might lead to a malfunctioning receptor. The scientists found that, in both mice and people, the gene is active only in taste bud cells known to contain taste receptors. More work will still be required in order to nail down the idea that the gene gives rise to a sweet receptor, Buck and Margolskee said.
Sweetness is one of five recognized tastes.
Genes for bitter taste receptors were identified by Buck and several others last year. Salty and sour tastes are detected by a different kind of sensor, and the no one has identified the sour-detecting system yet. A fifth taste, called umami, is found in the flavoring monosodium glutamate and many protein-rich foods like meat, fish and cheese. Researchers reported last year that they'd found a probable umami receptor. Archives - Archives of past weeks' Daily Selected News Stories.