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That is why, when we have opened the first Paleogenetic Lab in
Kazakhstan, we decided to start to investigate the Human bone
remains from Botai to identify a possible genetic connection of
ancient Botai people with other ancient cultures and the modern
population of Kazakhstan. For this moment we produced genome-
wide data of two individuals affiliated with the Eneolithic Botai
culture: 1) man – find of 1983, sampling was done in North-
Kazakhstan Regional Museum Association, c. Petropavlovsk, 2015;
2) woman – find of 2016, taken from Botai expedition, 2017.
Radiocarbon analysis of female individual was conducted by the
CEZ Archaeometry gGmbH (Mannheim, Germany) and dated 3517-
3367 cal. BCE, a man individual was dated by 3632-3100 cal. BCE
(Levine, 1999). Anthropological study revealed that Botai skulls
represent a particular anthropological type, which was formed in
steppe part of Asia during the Eneolithic period – “Kazakh Steppe
type”.
We extracted genomic DNA from skeletal remains (teeth and
samples of Glenoid fossa from temporal bone), and sequenced using
the Illumina HiSeq 4000 platform. Indexed libraries were enriched
for about 1.2 million informative nuclear SNPs using the in-solution
capture method (“1240K capture”). Libraries were sequenced on the
either for single-end 75 bp (SE75) or paired-end 50 bp (PE50) cycles
following manufacturer’s protocols. Mitochondrial consensus
sequences were obtained by the log2fasta
program in Schmutzi with
the quality cutoff 10 and subsequently assigned to haplogroups using
HaploGrep2. Y haplogroups were assigned using the yHaplo
program. Bioinformation analysis of full genome data
(coverage of
1.240.000 SNPs) included the full genome data of 16 modern
populations and published data on 25 ancient populations from
different parts of Eurasia.
DNA-analyses (wide genome sequencing) revealed that
Eneolithic period man from settlement Botai, characterizes by Y-
chromosome haplotype R1b1a1 and mtDNA haplotype K1b2. Y-
chromosome haplotype R1b1a1 has an Asian origin that spread to the
west. K1b2 mtDNA haplotype, which is believed of Eastern
European origin, is very common
in the modern population of
Western Europe and America. Perhaps we obtained a first evidence
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of the mtDNA K1b2 haplotype appearance in Central Eurasia, in
Northern Kazakhstan, from where K1b2 had a wide spread to the
West (Europe) and small spread to the East (Altai). The Botai female
individual has Z1 mtDNA haplotype. This indicates the Asian origin
(mostly Siberian and South Ural regions) of maternal line of this
Botai woman.
The Eneolithic Botai individuals are closest to each other in the
PC space than to any other ancient or present-day individual, and are
in proximity to the upper Paleolithic Siberians from the Malta or
Afontova Gora archaeological sites. Botai represents a separate
group that has genetic similarity with both European and Asian
populations. The ancient Botai genomes suggest yet another layer of
admixture in inner Eurasia that involves Mesolithic hunter-gatherers
in Europe, the Upper Paleolithic southern Siberians and East Asians.
Admixture modeling of ancient and modern populations suggests an
overwriting of this ancient structure in the Altai-Sayan region by
migrations of wester steppe nomads, but partial retaining of this
ancient North Eurasian-related cline further north.
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