a1 Department of Zoology, NJ-15, University of Washington, Seattle, WA 98195, U.S.A.
A method is introduced that allows the simplification of the calculation of equilibrium solutions in multiple locus genetic models of a single infinite population. The method can be applied when the number of different fitnesses is equal to or less than one more than the number of independent allelic frequencies. The results are in terms of relationships – the symmetry constraints – between the gametic frequencies that must be satisfied at any boundary or internal equilibrium. The symmetry constraints are independent of the fitness values and of the recombination fractions. This can lead to some understanding of the equilibrium structure of a model when the full equilibrium solution is not obtained and reduces the number of independent variables in the calculations of the full equilibrium solutions. Examples of two locus models with two alleles at each locus and with two alleles at one locus and three at the other are discussed.
(Received September 22 1978)