Pseudogenization of a sweet-receptor geneUnlike many animals, cats are indifferent to the sweet taste of sugar. Research reported by Li et al. suggests that the sweet receptor gene has become pseudogenized in the cat, rendering them "sweet-blind." The cover image is representational only, as the lynx depicted here, while a felid, was not a subject of the Li et al. study. The superimposed image shows part of the gene structure of the two genes that code for the sweet taste receptor dimer in the domestic cat, one of which contains a premature stop codon, rendering it nonfunctional.
Image Credit: Photograph by Erwin and Peggy Bauer, USFWS; line graphic by Felice Macera.