Calculating Allele Frequency in a Population

Definition: Allele frequency refers to the relative proportion of a specific allele in a population.

To calculate the frequency of allele p in the given population, we need to first determine the total number of alleles present in the population.

Step 1: Calculate total number of alleles in the population.
- Each homozygote individual (PP) has two copies of the P allele, so there are 2 x 2500 = 5000 P alleles.
- Each heterozygote individual (Pp) has one copy of the P allele, so there are 1 x 3000 = 3000 P alleles.
- The total number of P alleles is therefore 5000 + 3000 = 8000.
- Similarly, the total number of Q alleles is 2000 (since there are 2 Q alleles in each homozygote individual).

Step 2: Calculate the frequency of allele p.
- The frequency of allele p (represented by the letter 'p') is equal to the number of copies of the P allele divided by the total number of alleles in the population.
- In this case, there are 8000 P alleles and 10000 total alleles, so the frequency of allele p is 8000/10000 = 0.8.
- However, we need to remember that the frequency of p refers to the proportion of the population that carries the P allele, not the proportion of P alleles in the population.
- Since each homozygote individual (PP) carries two copies of the P allele, we need to count them only once.
- Therefore, the number of individuals carrying the P allele is 2500 (homozygotes) + 1500 (heterozygotes, since half of them carry the P allele) = 4000.
- The frequency of allele p can now be calculated as the proportion of individuals carrying the P allele in the population, which is 4000/10000 = 0.4.
- However, we are asked for the frequency of allele p specifically, not the frequency of individuals carrying the P allele.
- Since the frequency of the P allele is 0.4, the frequency of the Q allele (represented by the letter 'q') is 1 - 0.4 = 0.6.
- Therefore, the frequency of allele p is 0.6.