Question

In a population of tree frogs, the allele that causes yellow eyes (Y) is dominant over the allele that causes orange eyes (y). If 85% of the frogs have yellow eyes, what is the frequency of the dominant allele?

Answer 1

Allele that causes yellow eyes (Y) is dominant over the allele that causes orange eyes (y)

Y = 85% = 0.85 and

y = 100% - 85% = 15% = 0.15

f(y) = square root of y = √y = √0.15 = 0.387

frequency of the allele that causes orange eyes = 0.387

Once we know the value of y, Y + y = 1

Putting the value of y, we get

Y = 1 – 0.387

Frequency of the dominant allele that causes yellow eyes = 0.61