1. HardyWeinberg equilibrium In a population containing the genotype s of AA, aa, and Aa, the frequency of AA will be p2, the frequency of aa will be q2, and the frequency of Aa will be 2 pq at equilibrium, where p is the frequency of A and q is the frequency of a. By the HardyWeinberg law, a ramdonlymating population will eventually reach these frequencies and be at this equilibrium as long as there are no selection pressures on the population.
