Cytoplasm–chromosome interactions in Drosophila melanogaster

Abstract

INSTANCES of exceptionally high frequencies of mutation¹, male recombination², chromosomal aberration³ and sterility⁴ have been observed, often simultaneously^5–8, in many natural populations of Drosophila melanogaster during the past thirty years. In some cases^2,6,8, these exceptional phenomena seem to be associated with chromosomes but not necessarily with specific loci. Tests for an infectious agent have given negative results^2,4. Cytoplasmic factors, interacting with specific chromosomes, have been implicated in a few cases^4,7 but in many others the experimental design did not provide for their detection. We report large differences in male recombination and F₁ sterility between reciprocal crosses of strains derived from temporally and geographically diverse natural populations and several commonly-used laboratory marker and balancer stocks. Cytoplasm–chromosome interactions are suggested.