Human evolution in Siberia: from frozen bodies to ancient DNA

Eric Crubézy,Walther Parson,Christine Keyser,Martin Bodner,Morgane Gibert,Sylvain Amory,Caroline Bouakaze,Alexander Röck,Anatoly Alexeev,Bertrand Ludes

doi:10.1186/1471-2148-10-25

Abstract

BackgroundThe Yakuts contrast strikingly with other populations from Siberia due to their cattle- and horse-breeding economy as well as their Turkic language. On the basis of ethnological and linguistic criteria as well as population genetic studies, it has been assumed that they originated from South Siberian populations. However, many questions regarding the origins of this intriguing population still need to be clarified (e.g. the precise origin of paternal lineages and the admixture rate with indigenous populations). This study attempts to better understand the origins of the Yakuts by performing genetic analyses on 58 mummified frozen bodies dated from the 15th to the 19th century, excavated from Yakutia (Eastern Siberia).ResultsHigh quality data were obtained for the autosomal STRs, Y-chromosomal STRs and SNPs and mtDNA due to exceptional sample preservation. A comparison with the same markers on seven museum specimens excavated 3 to 15 years ago showed significant differences in DNA quantity and quality. Direct access to ancient genetic data from these molecular markers combined with the archaeological evidence, demographical studies and comparisons with 166 contemporary individuals from the same location as the frozen bodies helped us to clarify the microevolution of this intriguing population.ConclusionWe were able to trace the origins of the male lineages to a small group of horse-riders from the Cis-Baïkal area. Furthermore, mtDNA data showed that intermarriages between the first settlers with Evenks women led to the establishment of genetic characteristics during the 15th century that are still observed today.

Highlights

The Yakuts contrast strikingly with other populations from Siberia due to their cattle- and horsebreeding economy as well as their Turkic language
Recent population genetics data tend to support a dual origin for the maternal lineages of the Yakuts and admixture with the Tungus, and demonstrate that the paternal lines observed today result from a strong bottleneck that led to the restriction of these lineages in the Yakut population [3,4,6]
Data authenticity from the frozen bodies was determined by the concordance of morphological and molecular typing for sex determination, reproducible (Polymerase chain reaction) (PCR) results from multiple extractions, and the amplification and analysis of autosomal (Short Tandem Repeats) (STRs) markers based on their ability to detect degraded and/or contaminated DNA

Summary

Introduction

The Yakuts contrast strikingly with other populations from Siberia due to their cattle- and horsebreeding economy as well as their Turkic language. Recent population genetics data tend to support a dual origin for the maternal lineages of the Yakuts and admixture with the Tungus, and demonstrate that the paternal lines observed today result from a strong bottleneck that led to the restriction of these lineages in the Yakut population [3,4,6]. This does not, address the question of the number of settlers and the precise origin of the paternal lineages, or the admixture rate with indigenous populations [6]. Ancient DNA (aDNA), which allows the direct study of an ancient population without their descendants, represents a major advantage in order to avoid the possible bias represented by recent genetic events [8,9]

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