Recovering population parameters from a single gene genealogy: an unbiased estimator of the growth rate

Citation:

Maruvka YE, Shnerb NM, Bar-Yam Y, Wakeley J. Recovering population parameters from a single gene genealogy: an unbiased estimator of the growth rate. Mol. Biol. Evol. 2011;28 (5) :1617-1631.
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Abstract:

We show that the number of lineagesancestral to a sample, as a function of time back into the past, which we call the number
of lineages as a function of time (NLFT), is a nearly deterministic property of large-sample gene genealogies. We obtain analytic
expressionsfor the NLFT for both constant-sizedand exponentiallygrowing populations.The low level of stochastic variation
associated with the NLFT of a large sample suggests using the NLFT to make estimates of population parameters. Based on
this, we develop a new computational method of inferring the size and growth rate of a population from a large sample of
DNA sequences at a single locus. We apply our method first to a sample of 1,212 mitochondrial DNA (mtDNA) sequences
from China, confirming a pattern of recent population growth previously identified using other techniques, but with much
smaller confidence intervals for past population sizes due to
the low variation of the NLFT. We further analyze a set of 63
mtDNA sequences from blue whales (BWs), concluding that the population grew in the past. This calls for reevaluation of
previous studies that were based on the assumption that the BW population was fixed.

Last updated on 09/28/2015