A cytological F1 RNAi screen for defects in Drosophila melanogaster female meiosis.

Genetic screens for recessive alleles induce mutations, make the mutated chromosomes homozygous, and then assay those homozygotes for the phenotype of interest. When screening for genes required for female meiosis, the phenotype of interest has typically been nondisjunction from chromosome segregation errors. As this requires that mutant females be viable and fertile, any mutants that are lethal or sterile when homozygous cannot be recovered by this approach.

A Cytological F1 RNAi Screen for Defects in Female Meiosis.

Genetic screens for recessive alleles induce mutations, make the mutated chromosomes homozygous, and then assay those homozygotes for the phenotype of interest. When screening for genes required for female meiosis, the phenotype of interest has typically been nondisjunction from chromosome segregation errors. As this requires that mutant females be viable and fertile, any mutants that are lethal or sterile when homozygous cannot be recovered by this approach.

Comparative Cytology of Female Meiosis I Among Species.

The physical connections established by recombination are normally sufficient to ensure proper chromosome segregation during female Meiosis I. However, nonexchange chromosomes (such as the Muller element or "dot" chromosome in can still segregate accurately because they remain connected by heterochromatic tethers. A recent study examined female meiosis in the closely related species and , and found a nearly twofold difference in the mean distance the obligately nonexchange dot chromosomes were separated during Prometaphase.