The ability to taste the bitter compound phenylthiocarbamide (PTC) is an autosomal dominant trait. The inability to taste PTC is a recessive condition. In a sample of 500 people, 360 have the ability to taste PTC and 140 do not. Calculate the frequency of the recessive allele

Key Concepts

Autosomal Dominance and Recessiveness

Autosomal dominance refers to a pattern of inheritance where only one copy of a dominant allele is needed for the trait to be expressed. In contrast, a recessive trait requires two copies of the recessive allele for expression. In this case, the ability to taste PTC is dominant, while the inability to taste it is recessive.

Hardy-Weinberg Principle

The Hardy-Weinberg principle provides a mathematical framework for understanding allele frequencies in a population. It states that allele and genotype frequencies will remain constant from generation to generation in the absence of evolutionary influences. This principle is essential for calculating allele frequencies, including the frequency of the recessive allele in this scenario.

Allele Frequency Calculation

Allele frequency is the proportion of a specific allele among all allele copies in a population. To calculate the frequency of the recessive allele, we can use the number of individuals expressing the recessive phenotype and apply the Hardy-Weinberg equation. In this case, knowing the total number of individuals and the number of tasters allows us to derive the frequency of the recessive allele responsible for the inability to taste PTC.