Related Experiment Video
Updated: May 22, 2026

In Vivo Functional Study of Disease-associated Rare Human Variants Using Drosophila
Published on: August 20, 2019
Homologue pairing in flies and mammals: gene regulation when two are involved
Manasi S Apte1, Victoria H Meller
1Department of Biological Sciences, Wayne State University, Detroit, MI 48202, USA.
Abstract:
Chromosome pairing is usually discussed in the context of meiosis. Association of homologues in germ cells enables chromosome segregation and is necessary for fertility. A few organisms, such as flies, also pair their entire genomes in somatic cells. Most others, including mammals, display little homologue pairing outside of the germline. Experimental evidence from both flies and mammals suggests that communication between homologues contributes to normal genome regulation. This paper will contrast the role of pairing in transmitting information between homologues in flies and mammals. In mammals, somatic homologue pairing is tightly regulated, occurring at specific loci and in a developmentally regulated fashion. Inappropriate pairing, or loss of normal pairing, is associated with gene misregulation in some disease states. While homologue pairing in flies is capable of influencing gene expression, the significance of this for normal expression remains unknown. The sex chromosomes pose a particularly interesting situation, as females are able to pair X chromosomes, but males cannot. The contribution of homologue pairing to the biology of the X chromosome will also be discussed.
Related Concept Videos
Position-effect Variegation
Dosage Compensation
In addition to sexual development, the X chromosome has genes involved in autosomal functions such as brain development and the immune system. Therefore, males and females with distinct numbers of X chromosomes will have...
Cis-regulatory Sequences
The Ratio of X Chromosome to Autosomes
Normal male Drosophila has a ratio of one X chromosome to two sets of autosomes. In contrast, normal female Drosophila...
Exon Recombination
Exon shuffling follows “splice frame rules.” Each exon has three reading...
Gene Families
Occasionally these regions can be adapted to take on new roles within the organism, becoming novel genes...

