Question

1. consider a specific gene with two different alleles (y and y). if there are 4 homozygous dominant and 3 homozygous recessive individuals, what is the frequency of the dominant and recessive alleles?

Explanation:

Step1: Calculate total number of alleles

The total number of individuals is \(4 + 3=7\). Since each individual has 2 alleles for the gene, the total number of alleles is \(2\times7 = 14\).

Step2: Calculate number of dominant alleles

The 4 homozygous - dominant individuals (\(YY\)) contribute \(2\times4 = 8\) dominant alleles (\(Y\)). There are no heterozygous individuals considered for now, so the number of dominant alleles (\(Y\)) is 8.

Step3: Calculate frequency of dominant allele

The frequency of the dominant allele (\(p\)) is \(\frac{8}{14}=\frac{4}{7}\approx0.571\).

Step4: Calculate number of recessive alleles

The 3 homozygous - recessive individuals (\(yy\)) contribute \(2\times3 = 6\) recessive alleles (\(y\)).

Step5: Calculate frequency of recessive allele

The frequency of the recessive allele (\(q\)) is \(\frac{6}{14}=\frac{3}{7}\approx0.429\).

Answer:

The frequency of the dominant allele is \(\frac{4}{7}\approx0.571\) and the frequency of the recessive allele is \(\frac{3}{7}\approx0.429\).