Mitochondrial genomes uncover the maternal history of the Pamir populations

Abstract

The Pamirs, among the world's highest mountains in Central Asia, are one of homelands with the most extreme high altitude for several ethnic groups. The settlement history of modern humans on the Pamirs remains still opaque. Herein, we have sequenced the mitochondrial DNA (mtDNA) genomes of 382 individuals belonging to eight populations from the Pamirs and the surrounding lowlands in Central Asia. We construct the Central Asian (including both highlanders and lowlanders) mtDNA haplogroup tree at the highest resolution. All the matrilineal components are assigned into the defined mtDNA haplogroups in East and West Eurasians. No basal lineages that directly emanate from the Eurasian founder macrohaplogroups M, N, and R are found. Our data support the origin of Central Asian being the result of East-West Eurasian admixture. The coalescence ages for more than 93% mtDNA lineages in Central Asians are dated after the last glacial maximum (LGM). The post-LGM and/or later dispersals/admixtures play dominant roles in shaping the maternal gene pool of Central Asians. More importantly, our analyses reveal the mtDNA heterogeneity in the Pamir highlanders, not only between the Turkic Kyrgyz and the Indo-European Tajik groups, but also among three highland Tajiks. No evidence supports positive selection or relaxation of selective constraints in the mtDNAs of highlanders as compared to that of lowlanders. Our results suggest a complex history for the peopling of Pamirs by multiple waves of migrations from various genetic resources during different time scales.

Novel insight into the genetic basis of high-altitude pulmonary hypertension in Kyrgyz highlanders

“…S1). The admixture from East and West is consistent with the mitochondrial DNA ancestry analysis of the Kyrgyz highlanders [30]. No sign of shared ancestry was detected with YRI (two sample Kolmogorov-Smirnov P = 3.98E-20).…”

“…2a). Interestingly, despite the prehistoric and historic eastward migrations, the JPT proportion of admixture dominated both the mitochondrial/maternal lineage [30], as well as the nuclear DNA lineage ( Fig. 2a).…”

Spirometry in Central Asian Lowlanders and Highlanders, a Population Based Study

“…The Kyrgyz Republic, as an example of Central Asian states, is home to more than six million inhabitants (10) and around 41% of the population live higher than 1,000 m above sea level (11). A complex history of colonization with multiple waves of migration from East and West has resulted in a heterogeneous mix of races and ethnicities living in Central Asia (12)(13)(14). While spirometry reference values calculated from measurements in 1,044 Kyrgyz male miners (15) and from Kazak children (16) have been reported, spirometric reference data of a large Central Asian population sample of healthy, non-smoking adults-especially those of women-are lacking.…”

Mitochondrial DNA genomes revealed different patterns of high-altitude adaptation in high-altitude Tajiks compared with Tibetans and Sherpas

“…Recently, a study analyzed mtDNA genomes in different populations in Central Asia located around the Pamirs 18 , and different populations of Tajiks living at high altitude were also investigated. Because partial mtDNA sequences are not able to provide enough information, so complete mtDNA genome sequences were required for this research.…”

“…To better understand the genetic structure of the mtDNA genome and identify the possible role of the mtDNA genome in high-altitude adaptation in HA-Tajiks, 80 HA-Tajik individuals living in Taxkorgan were enrolled, and their whole mtDNA genomes were sequenced. We also examined the mtDNA genomes of Tibetans and Sherpas as well as other reported Tajik populations 18 to compare the genetic differences between them and to analyze different patterns of high-altitude adaptation between three high-altitude native populations at the Qinghai-Tibetan Plateau and in the Pamirs from perspectives of mtDNA variations.…”