Inheritance of Mitochondrial Mutations
The last decade has seen an astonishing growth of interest in diseases caused by mitochondrial mutations, and understanding the rules and mechanisms of their inheritance has acquired an increased urgency. This knowledge of transmission genetics is essential for accurate diagnosis, prognosis, genetic counseling, and genetic epidemiology. Remarkably, the best way to think about mitochondrial gene inheritance is in terms of populations of organelle genes inside single cells, subject to mutation, selection and random drift. Some of the models and equations of classical population genetics apply to these intracellular populations of organelle genes. Human geneticists do not have to understand much of the mathematics in order to understand the inheritance of mitochondria, but it is necessary to think clearly about the intracellular populations of mitochondrial genomes and the interactions between mutation, drift, and selection. In this review I will discuss what is known about the mechanics of mitochondrial DNA (mtDNA) inheritance in humans and the simple mathematical models that can be used to inform research and medical practice. An important take-home lesson is that seemingly overly-simplified stochastic models have considerable predictive as well as explanatory power, but this power can only be harnessed if we have more and better measurements of the fundamental parameters of mitochondrial gene inheritance.
KeywordsMitochondrial Genome Intracellular Selection Random Drift Mitochondrial Mutation Organelle Genome
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