Hostname: page-component-8448b6f56d-c47g7 Total loading time: 0 Render date: 2024-04-23T13:06:18.664Z Has data issue: false hasContentIssue false

Microsatellite variation among divergent populations of stalk-eyed flies, genus Cyrtodiopsis

Published online by Cambridge University Press:  12 October 2004

TIMOTHY F. WRIGHT
Affiliation:
Department of Biology, University of Maryland, College Park, MD 20742, USA Current affiliation: Genetics Program, NMNH, Smithsonian National Zoo, 3001 Connecticut Ave., Washington DC 20008, USA
PHILIP M. JOHNS
Affiliation:
Department of Biology, University of Maryland, College Park, MD 20742, USA
JAMES R. WALTERS
Affiliation:
Current affiliation: Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY 14853-2701, USA
ADAM P. LERNER
Affiliation:
Department of Biology, University of Maryland, College Park, MD 20742, USA
JOHN G. SWALLOW
Affiliation:
Department of Biology, University of Maryland, College Park, MD 20742, USA Current affiliation: Department of Biology, University of South Dakota, Vermillion, SD 57069, USA
GERALD S. WILKINSON
Affiliation:
Department of Biology, University of Maryland, College Park, MD 20742, USA
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Microsatellite primers are often developed in one species and used to assess neutral variability in related species. Such analyses may be confounded by ascertainment bias (i.e. a decline in amplification success and allelic variability with increasing genetic distance from the source of the microsatellites). In addition, other factors, such as the size of the microsatellite, whether it consists of perfect or interrupted tandem repeats, and whether it is autosomal or X-linked, can affect variation. To test the relative importance of these factors on microsatellite variation, we examine patterns of amplification and allelic diversity in 52 microsatellite loci amplified from five individuals in each of six populations of Cyrtodiopsis stalk-eyed flies that range from 2·2% to 11·2% mitochondrial DNA sequence divergence from the population used for microsatellite development. We find that amplification success and most measures of allelic diversity declined with genetic distance from the source population, in some cases an order of magnitude faster than in birds or mammals. The median and range of the repeat array length did not decline with genetic distance. In addition, for loci on the X chromosome, we find evidence of lower observed heterozygosity compared with loci on autosomes. The differences in variability between X-linked and autosomal loci are not adequately explained by differences in effective population sizes of the chromosomes. We suggest, instead, that periodic selection events associated with X-chromosome meiotic drive, which is present in many of these populations, reduces X-linked variation.

Type
Research Article
Copyright
2004 Cambridge University Press