The impact of darwinian evolution on medicine: the maternal side of the story.

Complex disorders are common in the human population and are caused by interplay between genetic and environmental factors. Therefore the quest for the genetic basis of such disorders has much similarity to deciphering the genetic basis of macro-evolutionary processes, such as speciation. Here I discuss conceptual connections between the principles underlying and processes occurring in disease and evolution. Special focus is given to the tremendous mitochondrial genetic variability in the population and within individuals and the impact of both types of variability on evolutionary processes and diseases.