Q.
At a particular locus, frequency of allele A is 0.6 and that of allele a is 0.4. What would be the frequency of heterozygotes in a random mating population at equilibrium?
In a stable population, for a gene with two alleles, 'A' (dominant) and 'a' (recessive), if the frequency of 'A' is p and the frequency of 'a' is q, then the frequencies of the three possible genotypes (AA, Aa and aa) can be expressed by the Hardy-Weinberg equation: p2+2pq+q2=1
where p2 = Frequency of AA (homozygous dominant) individuals q2 = Frequency of aa (homozygous recessive) individuals 2pq = Frequency of Aa (heterozygous) individuals
so, p=0.6 and q=0.4 (given) ∴2pq (frequency of heterozygote) =2×0.6×0.4 =0.48