Ovary Transplants in Drosophila Melanogaster: Meiosis and Crossing-Over in Superfemales

Abstract

Individuals of Drosophila melanogaster with three X-chromosomes and two sets of autosomes were called "superfemales" by Bridges [1]. They occur among the progeny of triploid females mated to diploid males [1], among the offspring of attached-X diploid females mated to diploid males [2], and under certain other conditions. Superfemales are low in viability as compared with normal diploid individuals and are always sterile. With the development of a simple method of transplantation for use in studies of Drosophila [3] and with the demonstration that offspring can be obtained from transplanted ovaries [4,5], the authors were led to investigate the possibility of obtaining progeny from superfemales by transplanting their ovaries to normal females. Aside from its bearing on the problem of the nature of sterility in the superfemale, such a study might, if it provided a method of obtaining progeny from superfemales, furnish a useful means of studying chromosome pairing and crossing-over among three homologous chromosomes under conditions less complicated than those in the triploid where the manner of disjunction of the autosomes is known to be related to crossing-over in the X-chromosomes [6]. Actually, although offspring can be obtained from superfemales by transplantation, the results are such that the use of the method as a means of studying such problems as crossing-over is strictly limited.