According to the Hardy-Weinberg law, the genotype frequencies of dominant homozygotes, heterozygotes, and recessive homozygotes are represented by p2, q2, and 2pq, respectively, where p is the frequency of the dominant allele and q is the frequency of the recessive allele. Explain how this formula was derived

Question

What will be an ideal response?

Answer 1

In Hardy–Weinberg calculations, p represents the frequency of the dominant allele and q represents the frequency of the recessive allele. Because the sum of p and q represents 100% of the alleles for that gene in the population, p + q = 1 . A Punnett square can be used to predict the genotypes produced by the random combination of these gametes. A look at the Punnett square shows that the frequency of homozygous genotypes with two copies of the dominant allele is represented as p2 , because p X p= p2; the frequency of heterozygous genotypes with one copy of each allele is represented as 2pq (pq + qp); and the frequency of homozygous recessive genotypes is represented as q2 because q X q= q2 . When added together, the frequencies of these three genotypes represent 100% of the genotypes for this gene in the population