Discussion
The results of the experiment show that PAV/PAV genotypes have the largest density of fungiform papillae, supertasters with PAV/PAV will be more likely to taste the bitterness of the PTC test strip, and the PAV/PAV genotype subjects are most likely to find grapefruit juice not palatable. Analyzing the results of the the first phenotypic experiment, the PTC test strip experiment showed that all of the subjects with AVI/AVI could not taste the PTC, so they all assigned the value 1 to the bitterness of the strip. The PAV/AVI and the PAV/PAV groups did not have such uniform results due to differing rankings within their genotype group. The PAV/AVI group ranked an average of 2.13 and the PAV/PAV group ranked an average of 2.33 (Fig. 2). Not only are these values similar to each other but due to the variation of rankings within the respective groups, their error bars on Figure 2 overlapped, revealing there was not a significant statistical difference between between the abilities of the PAV/AVI and PAV/PAV groups to taste PTC. Thus, the PTC test only partially supports our first hypothesis that supertasters would taste the highest degree of bitterness, followed by tasters, then nontasters because the there …show more content…
Figure 3 reveals that likelihood to find grapefruit juice non-palatable increased noticeably from the AVI/AVI to the PAV/AVI group; however, a significant increase cannot be seen between the PAV/AVI and the PAV/PAV groups. This suggests that palatability does not change between the taster and supertaster; only the nontaster shows a different--in this case lower--likelihood to find the grapefruit juice non-palatable. Thus, the palatability test only partially supports the third hypothesis that supertasters would be the most likely to find the grapefruit juice non-palatable, followed by tasters, then