Genetic analysis of the mutationFemale-lethalinDrosophila melanogaster

Abstract

SUMMARYA genetic analysis was made of theFemale-lethal(Fl) locus ofDrosophila melanogaster. This is anX-linked mutation which causes lethality only in females. Other alleles do not complementFland are either lethal or sterile when homozygous in females. Complementation studies onFlalleles demonstrate that there is no simple ranking of these alleles in terms of severity of phenotypic effect. Dosage manipulation ofFlalleles indicates that the sex-specificity is not a consequence of gene dosage effects. Viability studies on males carryingFlalleles show thatFlalleles have no effect on viability regardless of the presence or absence of aYchromosome. TheFllocus is therefore sex-specific. The hypothesis thatFl+ is involved in the establishment of imaginal phenotypic sex cannot be substantiated on the basis of experiments utilizing sex-change mutations.