Long microsatellites and unusually high levels of genetic diversity in the Orthoptera
Article first published online: 29 DEC 2011
Published 2011. This article is a U.S. Government work and is in the public domain in the USA.
Insect Molecular Biology
Volume 21, Issue 2, pages 181–186, April 2012
How to Cite
Chapuis, M.-P., Streiff, R. and Sword, G. A. (2012), Long microsatellites and unusually high levels of genetic diversity in the Orthoptera. Insect Molecular Biology, 21: 181–186. doi: 10.1111/j.1365-2583.2011.01124.x
- Issue published online: 8 MAR 2012
- Article first published online: 29 DEC 2011
- repeat number
Much remains to be learned about the mutational processes governing the evolution of microsatellite repeat regions and the associated levels of genetic diversity observed at microsatellite markers across populations or species. An extensive survey of microsatellite variation in 210 insect species from six major orders revealed that within Orthopterans, which are characterized by giant genomes, levels of genetic diversity were ∼20% higher and microsatellite repeat arrays were longer than in any other group. Because of the mutation dependence on repeat length, this result suggests a higher microsatellite loci mutation rate in the Orthoptera. We deem it plausible that differences among insect orders, either in mismatch repair systems or in abundance of transposable element-derived microsatellites, can shape the size distribution of both genomes and microsatellite repeat regions. Our findings emphasise that observed levels of genetic diversity can greatly vary across species (orders at least) because of molecular differences in the mechanisms that determine microsatellite size, and are therefore critical to conservation and population genetics studies, where microsatellite repeat variability is primarily interpreted in terms of population demography and history.