Genetic Equilibrium

The Hardy-Weinberg formula is used to establish allele frequencies at genetic equilibrium (no evolution), which is possible under these conditions:

• No mutations are occurring.
• The population is very, very large.
• The population is isolated from other populations of the same species (no immigration or emigration).
• All members survive and reproduce (no selection).
• Mating is completely random.

The Hardy-Weinberg formula

At genetic equilibrium, proportions of genotypes at a locus with two alleles are given by the equation:

p² AA + 2pq Aa + q2 aa = 1

Frequency of allele A = p

Frequency of allele a = q

This figure illustrates the Hardy-Weinberg formula.

This figure illustrates the concept of no change through generations.

Don't freak out over Hardy-Weinberg you won't have to actually work any math problems. Take a look at this tutorial and it will make a lot more sense. For me, this tutorial did not work in Mozilla on the student PC's in the basement of Hutchison. It worked fine with Internet Explorer.

The only possible test question on Hardy Weinberg is the one below. Feel better now?

REVIEW: The Hardy-Weinberg formula
Answer is useful in determining the extent to which a sexually reproducing population is evolving.