The FY3 gene plays a role in immune responses in flies In on

The FY3 gene plays a role in immune responses in flies. In one population, there are two alleles, and the frequency of one allele is 0.8. If the population is at Hardy–Weinberg equilibrium, how many homozygotes for the most common allele should we observe in a sample of 250 individuals?

10

40

80

120

160

I need explantion and calculations plz

Solution

According to Hardy-Weinberg principle, the frequency of alleles and genotype frequency in an uninfluenced population is constant. The dominant allele is represented by p and the recessive by q. the sum of both the alleles p+q=1 i.e, 100% usually, a recessive allele is more frequent in a population.Then let\'s say q=0.8 p+q=1 ; p=1-0.8 = 0.2 Number of organisms with homozygous or heterozygous phenotype with the formula p2+2pq+q2=1 the most common allele here is q. so from the equation q2 gives us the percentage of the population which are homozygous for q allele so then q2=(0.8)2 =0.64 and hence 64% of the population are homozygous. Here we have calculated for 100 individuals i.e, 64 out of but we are yet to find out of 250 what is the number of individuals 64x250/100 =160.