ooding-than the other well-characterized bitter taste receptor: TAS2R38, for PTC. The allele distribution for TAS2R38 demonstrates balancing selection, maintaining two distinct alleles in populations, which may allow a greater range of bitter taste recognition, according to a paper Wooding and Drayna published last year.
According to Glendinning and Drayna, experiments must now be conducted on humans to confirm the functional effect of the variants. "It's a big jump from a...cell expressing a particular G protein-coupled receptor [to] the human brain," Glendinning said. Coauthor Bernd Bufe, of the German Institute of Human Nutrition, said the team will use "taste tests to determine threshold levels" as he did in a previous paper.
"One of the very nice things about this study is that it suggests a very concrete hypothesis that might be tested in populations where malaria is present," Wooding told The Scientist. "It would be very interesting to return to those populations and find out whether people who are more or less sensitive to these compounds really do eat more of these plant compounds that protect them from malaria."
N. Soranzo et al., "Positive selection on a high-sensitivity allele of the human bitter-taste receptor TAS2R16," Current Biology, 15:1257-65, July 26, 2005.
John I. Glendinning
F. Jackson et al., "Two evolutionary models for the interactions of dietary cyanogens, hemoglobin S, and falciparum malaria." Am J. Human Biology, 2(5):521-532, May 1990.