Send to

Choose Destination
PLoS Genet. 2019 Nov 7;15(11):e1008421. doi: 10.1371/journal.pgen.1008421. eCollection 2019 Nov.

The joy of balancers.

Author information

Department of Medicine, Division of Medical Genetics, University of Washington, Seattle, Washington, United States of America.
Department of Pediatrics, Division of Genetic Medicine, University of Washington, Seattle, Washington and Seattle Children's Hospital, Seattle, Washington, United States of America.
Department of Biology, Indiana University, Bloomington, Indiana, United States of America.
Stowers Institute for Medical Research, Kansas City, Missouri, United States of America.
Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, Kansas, United States of America.


Balancer chromosomes are multiply inverted and rearranged chromosomes that are widely used in Drosophila genetics. First described nearly 100 years ago, balancers are used extensively in stock maintenance and complex crosses. Recently, the complete molecular structures of several commonly used balancers were determined by whole-genome sequencing. This revealed a surprising amount of variation among balancers derived from a common progenitor, identified genes directly affected by inversion breakpoints, and cataloged mutations shared by balancers. These studies emphasized that it is important to choose the optimal balancer, because different inversions suppress meiotic recombination in different chromosomal regions. In this review, we provide a brief history of balancers in Drosophila, discuss how they are used today, and provide examples of unexpected recombination events involving balancers that can lead to stock breakdown.

Conflict of interest statement

The authors have declared that no competing interests exist.

Publication type

Publication type

Supplemental Content

Full text links

Icon for Public Library of Science Icon for PubMed Central
Loading ...
Support Center