Question

. Some people taste the chemical phenylthiocarbamide (PTC) as intensely bitter, while others cannot taste it at all. PTC is similar to chemicals in broccoli, Brussels sprouts, and cabbage, among other plants. Tasting PTC is a dominant trait; non-tasting is recessive. About 51% of people of European descent are tasters. If all of the assumptions of Hardy-Weinberg equilibrium are met, then among people of European descent... a) What is the frequency of the non-taster phenotype

Answer 1

The frequency of the non-taster phenotype among people of European descent is 49% or 0.49

Step-by-step explanation:

Let us assume that the allele for tasting PTC is T, while that for not tasting PTC is t.

According to the Hardy-Weinberg equation : p² + 2pq + q² = 1

Also p + q = 1

Where p² is the frequency of individuals with the TT genotype for tasting PTC,; wow is the frequency of individuals with the heterozygous allele for tasting PTC, while q² is the frequency of the individuals with tt genotype expressed as the non-taster phenotype since the allele for tasting is dominant over that of the non-taster.

From the information provided 51% of people of European descent are tasters. Also, tasting PTC is dominant over non-tasting. This implies that individuals with TT genotype and Tt genotype will be phenotypically expressed as tasters.

Therefore p² + 2pq = 51% or 0.51

q² = 1 - p² + 2pq

q² = 1 - 0.51

q² = 0.49 or 49%

The frequency of the non-taster phenotype among people of European descent is 49% or 0.49