title: Estimation of Fitness Components in DROSOPHILA MELANOGASTER. II. Influence of Reduced Transmission Frequency.
abstract: Results are presented of further analyses of the significant effects of reciprocal crosses reported by Katz and Cardellino (1978) in regard to viability indices of wild-type second chromosome heterozygotes. The observed differences between reciprocal crosses can be explained by the existence of reduced transmission frequencies of the wild-type homologue from Pm/+ and Cy/+ paternal parents. Mean estimates of transmission frequencies from Pm/+ and Cy/+ males in California and Japan populations are significantly less than the Mendelian expectation of 1/2. The transmission frequencies of +(i) chromosomes from Pm/+(i) and Cy/+(i) males are also found to be positively correlated in the California and pooled populations, suggesting that the degree of distortion is primarily due to the +(i) chromosome rather than to Cy or Pm. A sufficient estimator of relative viability that is independent of distorted transmission frequencies is derived for use in the Cy/Pm technique of viability estimation.
authors.affiliation: Department of Biological Sciences, Illinois State University, Normal, Illinois 61761.
authors.forename: A J
authors.initials: AJ
authors.lastname: Katz