In a study of a population of bluefooted boobiesan actual bi

In a study of a population of blue-footed boobies(an actual bird!) that is in Hardy-Weinberg equilibrium, you find that 72% of the boobies have the dominant blue-foot phenotype. Foot color is determined by a single autosomal gene for which there are two alleles. What would be the percentage of heterozygotes in the population? (remember to show ALL work for credit; round to nearest hundredth)

Solution

Answer: 50%

Explanation

Dominant = blue

Recessive = normal

Dominant = 72%

Recessive= 28%

The frequency of recessive phenotype (q^2) = 28/100= 0.28

The frequencey of recessive allele = sqrt of 0.28 = 0.53

As p+q= 1

p+0.53= 1

p = 1-0.53= 0.47

The heterozygous frequency = 2pq = 2 * 0.47 * 0.53 = 0.5

The heterozygous population = 2pq * 100 = 0.5 * 100 = 50%