The Genetic Structure of Natural Populations of DROSOPHILA MELANOGASTER. Xiv. Effects of the Incomplete Dominance of the IN(2LR)SM1 (Cy) Chromosome on the Estimates of Various Genetic Parameters.

Recent reports (Mukaiet al. 1974; Katz and Cardellino 1978; Cockerham and Mukai 1978) have indicated that the Cy chromosome is not always dominant over its homologous chromosome with respect to viability. Thus, the genetic parameters previously estimated using viabilities determined by the Cy method are biased. In the present paper, the biases of the estimates for the polygenic mutation rate, the degree of dominance and the homozygous load are examined. The results indicate that the biases for the mutation rate and the degree of dominance are small and that the estimate of the homozygous load relative to the average viability of the population is not biased.