Iron Age and Anglo-Saxon genomes from East England reveal British migration history.

Stephan Schiffels,Wolfgang Haak,Duncan Sayer,Louise Loe,Alice Lyons,Chris Tyler-Smith,Rachel Clarke,Alan Cooper,Pirita Paajanen,Elizabeth Popescu,Bastien Llamas,Richard Mortimer,Richard Durbin

doi:10.1038/ncomms10408

Abstract

British population history has been shaped by a series of immigrations, including the early Anglo-Saxon migrations after 400 CE. It remains an open question how these events affected the genetic composition of the current British population. Here, we present whole-genome sequences from 10 individuals excavated close to Cambridge in the East of England, ranging from the late Iron Age to the middle Anglo-Saxon period. By analysing shared rare variants with hundreds of modern samples from Britain and Europe, we estimate that on average the contemporary East English population derives 38% of its ancestry from Anglo-Saxon migrations. We gain further insight with a new method, rarecoal, which infers population history and identifies fine-scale genetic ancestry from rare variants. Using rarecoal we find that the Anglo-Saxon samples are closely related to modern Dutch and Danish populations, while the Iron Age samples share ancestors with multiple Northern European populations including Britain.

Highlights

British population history has been shaped by a series of immigrations, including the early Anglo-Saxon migrations after 400 CE
We generated genome sequences for 10 samples that were collected from three sites in East England close to Cambridge: Hinxton, Oakington and Linton (1 sample), which were selected from a total of 23 screened samples based on DNA preservation (Fig. 1b, Table 1, Supplementary Table 1, Supplementary Note 1)
All sequenced samples were radiocarbon dated (Supplementary Table 2), and fall into three time periods: the Linton sample and two Hinxton samples are from the late Iron Age (B100 BCE), the four samples from Oakington from the early Anglo-Saxon period, and three Hinxton samples from the middle Anglo-Saxon period

Summary

Introduction

British population history has been shaped by a series of immigrations, including the early Anglo-Saxon migrations after 400 CE. By analysing shared rare variants with hundreds of modern samples from Britain and Europe, we estimate that on average the contemporary East English population derives 38% of its ancestry from Anglo-Saxon migrations. Within the last 2,000 years alone, the British Isles have received multiple well-documented immigrations These include military invasions and settlement by the Romans in the first century CE, peoples from the North Sea coast of Europe collectively known as the Anglo-Saxons between ca. If the source population is genetically close to the indigenous population, migrations are hard to quantify due to the challenge in detecting small genetic differences This is true for the case of the Anglo-Saxon migrations in Britain, given the close genetic relationships across Europe[9,10]. We give evidence for mixing of migrants and natives in the early Anglo-Saxon period, and we show that the Anglo-Saxon migrants studied here have close ancestry to modern-day Dutch and Danish populations

Methods

Results

Conclusion