Inferring human population size and separation history from multiple genome sequences

Abstract

Stephan Schiffels and Richard Durbin report the multiple sequentially Markovian coalescent (MSMC) method for inferring human population size and separation history from multiple genome sequences. Their application to the whole-genome sequences of 34 individuals from 9 populations allows inferences about events in human population history as recent as 2,000 years ago. The availability of complete human genome sequences from populations across the world has given rise to new population genetic inference methods that explicitly model ancestral relationships under recombination and mutation. So far, application of these methods to evolutionary history more recent than 20,000–30,000 years ago and to population separations has been limited. Here we present a new method that overcomes these shortcomings. The multiple sequentially Markovian coalescent (MSMC) analyzes the observed pattern of mutations in multiple individuals, focusing on the first coalescence between any two individuals. Results from applying MSMC to genome sequences from nine populations across the world suggest that the genetic separation of non-African ancestors from African Yoruban ancestors started long before 50,000 years ago and give information about human population history as recent as 2,000 years ago, including the bottleneck in the peopling of the Americas and separations within Africa, East Asia and Europe.