Variance component analysis of bristle characters in local populations of Drosophila melanogaster

The genetic variabilities of steroopleural and abdominal bristle numbers existing- in local natural populations were assessed. Using second chromosome lines of Drosophila melanogaster extracted from three natural populations in Japan (the Ishigakijima, Ogasawara and Aomori populations), experiments were conducted to estimate the components of genetic variances, additive and dominance variances. The following results were obtained: For both stemopleural and abdominal bristle numbers, the additive genetic variances (a'i) were much larger than the dominance variances (of,) especially in the southern populations. For example, in the Ishigakijima population, for females stemopleural bristle numbers of the inversion-free chromosome group, the additive and dominance.