Hypothesis and Theory ARTICLE
Varied mechanisms and models for the varying mitochondrial bottleneck
- 1University of Bergen, Norway
Mitochondrial DNA (mtDNA) molecules exist in populations within cells, and may carry mutations. Different cells within an organism, and organisms within a family, may have different proportions of mutant mtDNA in these cellular populations. This diversity is often thought of as arising from a ‘genetic bottleneck’. This article surveys approaches to characterise and model the generation of this genetic diversity, aiming to provide an introduction to the range of concepts involved, and to highlight some recent advances in understanding. In particular, differences between the statistical ‘genetic bottleneck’ (mutant proportion spread) and the physical mtDNA bottleneck and other cellular processes are highlighted. Particular attention is paid to the quantitative analysis of the ‘genetic bottleneck’, estimation of its magnitude from observed data, and inference of its underlying mechanisms. Evidence that the ‘genetic bottleneck’ (mutant proportion spread) varies with age, between individuals and species, and
across mtDNA sequences, is described. The interpretation issues that arise from sampling errors, selection, and different quantitative definitions are also discussed.
Keywords: mtDNA, Bottleneck, development, inheritance, modelling, uncertainty, heterogeneity
Received: 13 Aug 2019;
Accepted: 06 Nov 2019.
Copyright: © 2019 Johnston. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Dr. Iain Johnston, University of Bergen, Bergen, 5020, Hordaland, Norway, firstname.lastname@example.org