Mitochondrial DNA is unsuitable to test for isolation by distance
Peter R. Teske, Tirupathi Rao Golla, Jonathan Sandoval-Castillo, Arsalan Emami-Khoyi, Carl D. van der Lingen, Sophie von der Heyden, Brent Chiazzari, Bettine Jansen van Vuuren & Luciano B. Beheregaray
Scientific Reports volume 8, Article number: 8448 (2018)
Abstract
Tests for isolation by distance (IBD) are the most commonly used method of assessing spatial genetic structure. Many studies have exclusively used mitochondrial DNA (mtDNA) sequences to test for IBD, but this marker is often in conflict with multilocus markers. Here, we report a review of the literature on IBD, with the aims of determining (a) whether significant IBD is primarily a result of lumping spatially discrete populations, and (b) whether microsatellite datasets are more likely to detect IBD when mtDNA does not. We also provide empirical data from four species in which mtDNA failed to detect IBD by comparing these with microsatellite and SNP data. Our results confirm that IBD is mostly found when distinct regional populations are pooled, and this trend disappears when each is analysed separately. Discrepancies between markers were found in almost half of the studies reviewed, and microsatellites were more likely to detect IBD when mtDNA did not. Our empirical data rejected the lack of IBD in the four species studied, and support for IBD was particularly strong for the SNP data. We conclude that mtDNA sequence data are often not suitable to test for IBD, and can be misleading about species’ true dispersal potential. The observed failure of mtDNA to reliably detect IBD, in addition to being a single-locus marker, is likely a result of a selection-driven reduction in genetic diversity obscuring spatial genetic differentiation.
Acknowledgements
This study was funded by the National Research Foundation (CSUR Grant No. 87702 to P.R.T.), the University of Johannesburg (URC/FRC grant to P.R.T) and the Australian Research Council (FT130101068 and DP110101275 to L.B.B.). T.R.G. and A.E.-K. acknowledge the University of Johannesburg for Global Excellence and Stature (GES) fellowships for doctoral and postdoctoral study, respectively. We are grateful to two anonymous reviewers whose comments improved the quality of this manuscript.
Author information
Author notes
Peter R. Teske and Tirupathi Rao Golla contributed equally to this work.
Affiliations
Centre for Ecological Genomics and Wildlife Conservation, Department of Zoology, University of Johannesburg, Auckland Park, 2006, South Africa
Peter R. Teske, Tirupathi Rao Golla, Arsalan Emami-Khoyi & Bettine Jansen van Vuuren
Molecular Ecology Lab, College of Science and Engineering, Flinders University, Adelaide, SA, 5001, Australia
Jonathan Sandoval-Castillo & Luciano B. Beheregaray
Branch: Fisheries Management, Department of Agriculture, Forestry and Fisheries, Private Bag X2, Vlaeberg, 8012, South Africa
Carl D. van der Lingen
Department of Biological Sciences and Marine Research Institute, University of Cape Town, Private Bag X3, Rondebosch, 7700, South Africa
Carl D. van der Lingen
Evolutionary Genomics Group, Department of Botany and Zoology, University of Stellenbosch, Private Bag X1, 7602, Matieland, South Africa
Sophie von der Heyden
School of Life Sciences, University of KwaZulu-Natal, Westville, Durban, 4001, South Africa
Brent Chiazzari
Contributions
P.R.T. and L.B.B. designed the study; C.v.d.L., P.R.T., S.v.d.H., B.C. and J.S.-C. collected the samples; P.R.T. and T.R.G. conducted the literature review; P.R.T., J.S.-C., T.R.G. and A.E.-K. analysed the data; P.R.T., L.B.B., T.R.G. and S.v.d.H. wrote the paper, with input from C.v.d.L., J.S.-C., B.v.V. and B.C.
Competing Interests
The authors declare no competing interests.
Corresponding author
Correspondence to Peter R. Teske.
FREE PDF GRATIS: Scientific Reports Sup. Info.
