A genetic method for dating ancient genomes provides a direct estimate of human generation interval in the last 45,000 years.

Proc Natl Acad Sci U S A
Authors
Keywords
Abstract

The study of human evolution has been revolutionized by inferences from ancient DNA analyses. Key to these studies is the reliable estimation of the age of ancient specimens. High-resolution age estimates can often be obtained using radiocarbon dating, and, while precise and powerful, this method has some biases, making it of interest to directly use genetic data to infer a date for samples that have been sequenced. Here, we report a genetic method that uses the recombination clock. The idea is that an ancient genome has evolved less than the genomes of present-day individuals and thus has experienced fewer recombination events since the common ancestor. To implement this idea, we take advantage of the insight that all non-Africans have a common heritage of Neanderthal gene flow into their ancestors. Thus, we can estimate the date since Neanderthal admixture for present-day and ancient samples simultaneously and use the difference as a direct estimate of the ancient specimen's age. We apply our method to date five Upper Paleolithic Eurasian genomes with radiocarbon dates between 12,000 and 45,000 y ago and show an excellent correlation of the genetic and (14)C dates. By considering the slope of the correlation between the genetic dates, which are in units of generations, and the (14)C dates, which are in units of years, we infer that the mean generation interval in humans over this period has been 26-30 y. Extensions of this methodology that use older shared events may be applicable for dating beyond the radiocarbon frontier.

Year of Publication
2016
Journal
Proc Natl Acad Sci U S A
Volume
113
Issue
20
Pages
5652-7
Date Published
2016 May 17
ISSN
1091-6490
URL
DOI
10.1073/pnas.1514696113
PubMed ID
27140627
PubMed Central ID
PMC4878468
Links
Grant list
F32 GM115006 / GM / NIGMS NIH HHS / United States
R01 GM100233 / GM / NIGMS NIH HHS / United States
K99 GM111744 / GM / NIGMS NIH HHS / United States
R00 GM111744 / GM / NIGMS NIH HHS / United States
R01 GM083098 / GM / NIGMS NIH HHS / United States