Distribution of gene frequencies under the case of random genetic drift with and without selection

Studies by computer simulation to determine applicability of the theory of the distribution of gene frequencies at the steady state of decay to small populations and the effect of linkage on the distribution revealed: 1. For random genetic drift with no selection theory and observations agree well for independent assortment and linkage. 2. For random genetic drift with selection theory and observations agree well for independent assortment and full dominance. Linkage with relatively large N s decreased the mean gene frequency of unfixed classes and the steady rate of fixation of the favorable allele. 3. With independent assortment and additive gene effects agreement between theory and observations for the rates of fixation and loss at the terminal classes was good only for effective population number of at least 42. Small effective population numbers increased variance and decreased the steady rate of fixation and loss at the terminal classes. Linkage had no effect for small N s, but for relatively large N s, it decreased the mean of gene frequencies and increased the steady rate of fixation and loss at the terminal classes from that of independent assortment.