Post by Admin on Sept 30, 2021 4:03:47 GMT
The origin of Tibet highlanders
The peopling of the Tibetan Plateau is particularly important in
the study of the origin of the Japanese people, because previous
genetic studies highlighted a particular Ychromosomal haplogroup
(D-M174 or D1) that was shared
among Jomon, Tibetan, and Andamanese people (Underhill
et al., 2001; Thangaraj et al., 2003; Hammer et al., 2006; Shi
et al., 2008). Studies of mitochondrial haplotypes proposed
a dual-structure model of present-day Tibetans, parallel to
the situation in the Japanese archipelago (Qin et al., 2010; Li
et al., 2015). Autosomal genome studies also indicated the
Tibetan populations consist of the admixture of ancient Paleolithic
people and new Neolithic migrants; in particular, recent ancient-genome
sequencing showed that the Neolithic
migrants were closely related to Neolithic northern East
Asians in the Yellow River basin rather than the southern
East Asians (Lu et al., 2016; Wang et al., 2020b; Yang et al.,
2020). The pattern is consistent with a study proposing a
northern Chinese origin of Sino-Tibetan languages from
linguistic data (Zhang et al., 2019), although the inferred
pattern of gene flow from northern East Asia might have
been very complex, including multiple migration waves (Lu
et al., 2016; Wang et al., 2020a).
The origin of the Paleolithic Tibetan population, however,
remains unclear. Jeong et al. (2016) showed a deeply shared
ancestry between Sherpa and Ainu people using single nucleotide
polymorphism (SNP) chip data, consistent with
the Y-chromosomal pattern. In contrast, Kanzawa-Kiriyama
et al. (2019) did not detect a significant genetic tie between
Sherpa and Jomon people. A study by Yang et al. (2020) using
qpAdm analysis showed that Late Neolithic (Chokhopani) and
present-day Tibetans can be explained by the admixture between
northern East Asian (Boshan) and Jomon
(Ikawazu) individuals, supporting the deep genetic relationship
between present-day Japanese and Tibetans. A recent
unpublished study, analyzing many present-day and ancient
genome sequences in East Asia, suggested Hoabinhian/
Onge-related ancestry of Paleolithic Tibetans (Wang et al.,
2020a). Whether a basal population for present-day Tibetans
harbored a shared lineage with the ancestors of Jomon people
is not totally clear, but the above studies corroborate the
finding that present-day Tibetans have genetic components
of a deeply diverged basal Asian population.
Neolithic population history in East and Northeast Asia
The earliest complex civil communities in East Asia developed
in present-day China. Recent studies of ancient
DNA sequencing in Neolithic East and Northeast Asia revealed
insights into how the population structure in this region shifted
(Ning et al., 2020; Wang et al., 2020a; Yang et
al., 2020). Across the Northeast to South China and to Primorsky
in Russia, four major centers for Neolithic cultures
are recognized: the Amur River basin, the West Liao River (a
tributary of the Liao River) basin, the Yellow River basin,
and the Yangtze River basin (Figure 2). Although these four
centers developed with their own unique features, archeological
evidence implies that they were interconnected and
influenced each other (Shelach-Lavi, 2015).
Among the four centers, the people in the Amur River
basin showed the smallest amount of change in their genetic
features during the Neolithic/Bronze Age/Iron Age periods.
It has been shown that Early to Late Neolithic individuals in
the inland portion of the Amur River basin, as well as individuals
from the coastal Devil’s Gate (Figure 2), are genetically highly
similar to present-day Tungstic-speaking people, such as Ulchi,
Oroqen, and Hezhen (Nanai) people
(Siska et al., 2017; Ning et al., 2020). However, the effect
from Paleo-Siberians during the Paleolithic period is not
negligible. Present-day people in the Amur River basin share
slight but significant genetic drift with Paleo-Siberians. Using
a composite likelihood estimation based on the joint site
frequency spectrum, Sikora et al. (2019) reported that present-day
Siberians (Even) have a 3.9% admixture from a lineage related to the
Kolyma individual.
The peopling of the Tibetan Plateau is particularly important in
the study of the origin of the Japanese people, because previous
genetic studies highlighted a particular Ychromosomal haplogroup
(D-M174 or D1) that was shared
among Jomon, Tibetan, and Andamanese people (Underhill
et al., 2001; Thangaraj et al., 2003; Hammer et al., 2006; Shi
et al., 2008). Studies of mitochondrial haplotypes proposed
a dual-structure model of present-day Tibetans, parallel to
the situation in the Japanese archipelago (Qin et al., 2010; Li
et al., 2015). Autosomal genome studies also indicated the
Tibetan populations consist of the admixture of ancient Paleolithic
people and new Neolithic migrants; in particular, recent ancient-genome
sequencing showed that the Neolithic
migrants were closely related to Neolithic northern East
Asians in the Yellow River basin rather than the southern
East Asians (Lu et al., 2016; Wang et al., 2020b; Yang et al.,
2020). The pattern is consistent with a study proposing a
northern Chinese origin of Sino-Tibetan languages from
linguistic data (Zhang et al., 2019), although the inferred
pattern of gene flow from northern East Asia might have
been very complex, including multiple migration waves (Lu
et al., 2016; Wang et al., 2020a).
The origin of the Paleolithic Tibetan population, however,
remains unclear. Jeong et al. (2016) showed a deeply shared
ancestry between Sherpa and Ainu people using single nucleotide
polymorphism (SNP) chip data, consistent with
the Y-chromosomal pattern. In contrast, Kanzawa-Kiriyama
et al. (2019) did not detect a significant genetic tie between
Sherpa and Jomon people. A study by Yang et al. (2020) using
qpAdm analysis showed that Late Neolithic (Chokhopani) and
present-day Tibetans can be explained by the admixture between
northern East Asian (Boshan) and Jomon
(Ikawazu) individuals, supporting the deep genetic relationship
between present-day Japanese and Tibetans. A recent
unpublished study, analyzing many present-day and ancient
genome sequences in East Asia, suggested Hoabinhian/
Onge-related ancestry of Paleolithic Tibetans (Wang et al.,
2020a). Whether a basal population for present-day Tibetans
harbored a shared lineage with the ancestors of Jomon people
is not totally clear, but the above studies corroborate the
finding that present-day Tibetans have genetic components
of a deeply diverged basal Asian population.
Neolithic population history in East and Northeast Asia
The earliest complex civil communities in East Asia developed
in present-day China. Recent studies of ancient
DNA sequencing in Neolithic East and Northeast Asia revealed
insights into how the population structure in this region shifted
(Ning et al., 2020; Wang et al., 2020a; Yang et
al., 2020). Across the Northeast to South China and to Primorsky
in Russia, four major centers for Neolithic cultures
are recognized: the Amur River basin, the West Liao River (a
tributary of the Liao River) basin, the Yellow River basin,
and the Yangtze River basin (Figure 2). Although these four
centers developed with their own unique features, archeological
evidence implies that they were interconnected and
influenced each other (Shelach-Lavi, 2015).
Among the four centers, the people in the Amur River
basin showed the smallest amount of change in their genetic
features during the Neolithic/Bronze Age/Iron Age periods.
It has been shown that Early to Late Neolithic individuals in
the inland portion of the Amur River basin, as well as individuals
from the coastal Devil’s Gate (Figure 2), are genetically highly
similar to present-day Tungstic-speaking people, such as Ulchi,
Oroqen, and Hezhen (Nanai) people
(Siska et al., 2017; Ning et al., 2020). However, the effect
from Paleo-Siberians during the Paleolithic period is not
negligible. Present-day people in the Amur River basin share
slight but significant genetic drift with Paleo-Siberians. Using
a composite likelihood estimation based on the joint site
frequency spectrum, Sikora et al. (2019) reported that present-day
Siberians (Even) have a 3.9% admixture from a lineage related to the
Kolyma individual.
