Kuželov seminár

Wed 9 Mar. 2011, 14:00

Title: Bayesian inference of ancient human demography from individual genome sequences
Speaker: Adam Siepel, Cornell University

Complete genome sequences are now available for individuals from several
major human population groups.  Here we describe an effort to estimate key
evolutionary parameters from the complete genome sequences of six
individuals from six different populations.  Employing a Bayesian approach
based on coalescent theory, we extracted information about ancestral
population sizes, divergence times, and migration rates from inferred
genealogies at many neutrally evolving loci from across the genome.  To
analyze data from human individuals, we modified previous methods to
account for gene flow between populations and to integrate over possible
phasings of diploid genotypes.  We also developed a custom pipeline for
genotype inference to mitigate possible biases from heterogeneous
sequencing technologies, coverage levels, and read lengths.  We estimate
that the most recent common ancestral population of modern humans lived
108-157 thousand years ago (kya) and had an effective size of ~9,000, and
that Eurasian and West African populations diverged 38-64 kya.