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Western Kazakhstan is populated by three clans totaling 2 million people. Since the clans are patrilineal, the Y-chromosome is the most informative genetic system for tracing their origin. We genotyped 40 Y-SNP and 17 Y-STR markers in 330 Western Kazakhs. High phylogenetic resolution within haplogroup C2a1a2-M48 was achieved by using additional SNPs. Three lines of evidence indicate that the Alimuly and Baiuly clans (but not the Zhetiru clan) have a common founder placed 700 ± 200 years back by the STR data and 500 ± 200 years back by the sequencing data. This supports traditional genealogy claims about the descent of these clans from Emir Alau, who lived 650 years ago and whose lineage might be carried by two-thirds of Western Kazakhs. There is accumulation of specific haplogroups in the subclans representing other lineages, confirming that the clan structure corresponds with the paternal genetic structure of the steppe population.

Ubykh people inhabited the area of what now is Greater Sochi, one time being neighbors of the Abkhaz and Adyghe. In 1864, after the Caucasian War, a small group of Ubykh survivors migrated to Turkey. The Ubykh language is a branch of the Northwest Caucasian (Abkhazo-Adyghe) languages, which is either placed in the Abkhaz or Adyghe subgroup or distinguished in a separate subgroup, according to various classifications. All this makes Ubykhs an important but genetically unexplored part of the gene pool of the Caucasus population. We collected an exclusive sample (N = 36) of Ubykh individuals, mainly from their diaspora in Turkey. Application of a high resolution panel of Y-chromosome markers (59 SNP and 17 STR) revealed the major West Caucasus haplogroup G2 (75% of the Ubykh population) and pan-Eurasian haplogroup R1a (19%). Within the G2 haplogroup, we identified 14 branches and genotyped 14 branch-defining markers. The frequencies of the same 14 markers in 19 other populations of the Caucasus were included for comparison. Both the genetic distances and the gene geographical map of the most frequent subhaplogroup (defined by the YY1215 marker at the GRCh37 position 8903699, comprising 50% of the Ubykh sample) revealed similarity of the Ubykh and Adyghe populations. Other Abkhaz-Adyghe-speaking populations appear to be at a greater genetic distance from the Ubykhs, similar to the distance to the Turkic-speaking groups of the North Caucasus. The Ossetian gene pool has little in common with Ubykhs, thus contradicting the hypothesis of the Alanian substrate in Ubykhs. Other populations of the Caucasus and Transcaucasia (of Nakh-Daghestanian and Kartvelian linguistic groups) do not show apparent genetic similarities to Ubykhs.

Western Kazakhstan is populated by three clans totaling 2 million people. Since the clans are patrilineal, the Y-chromosome is the most informative genetic system for tracing their origin. We genotyped 40 Y-SNP and 17 Y-STR markers in 330 Western Kazakhs. High phylogenetic resolution within haplogroup C2a1a2-M48 was achieved by using additional SNPs. Three lines of evidence indicate that the Alimuly and Baiuly clans (but not the Zhetiru clan) have a common founder placed 700 ± 200 years back by the STR data and 500 ± 200 years back by the sequencing data. This supports traditional genealogy claims about the descent of these clans from Emir Alau, who lived 650 years ago and whose lineage might be carried by two-thirds of Western Kazakhs. There is accumulation of specific haplogroups in the subclans representing other lineages, confirming that the clan structure corresponds with the paternal genetic structure of the steppe population.

Y-chromosomal variation in West Asian populations has so far been studied in less detail than in the neighboring Europe. Here, we analyzed 598 Y-chromosomes from two West Asian subregions-Transcaucasia and the Armenian plateau-using 40 Y-SNPs and 17 Y-STRs and combined them with previously published data from the region. The West Asian populations fell into two clusters: upland populations from the Anatolian, Armenian and Iranian plateaus, and lowland populations from the Levant, Mesopotamia and the Arabian Peninsula. This geographic subdivision corresponds with the linguistic difference between Indo-European and Turkic speakers, on the one hand, and Semitic speakers, on the other. This subdivision could be traced back to the Neolithic epoch, when upland populations from the Anatolian and Iranian plateaus carried similar haplogroup spectra but did not overlap with lowland populations from the Levant. We also found that the initial gene pool of the Armenian motherland population has been well preserved in most groups of the Armenian Diaspora. In view of the contribution of West Asians to the autosomal gene pool of the steppe Yamnaya archaeological culture, we sequenced a large portion of the Y-chromosome in haplogroup R1b samples from present-day East European steppe populations. The ancient Yamnaya samples are located on the "eastern" R-GG400 branch of haplogroup R1b-L23, showing that the paternal descendants of the Yamnaya still live in the Pontic steppe and that the ancient Yamnaya population was not an important source of paternal lineages in present-day West Europeans.

E-M183 (E-M81) is the most frequent paternal lineage in North Africa and thus it must be considered to explore past historical and demographical processes. Here, by using whole Y chromosome sequences from 32 North African individuals, we have identified five new branches within E-M183. The validation of these variants in more than 200 North African samples, from which we also have information of 13 Y-STRs, has revealed a strong resemblance among E-M183 Y-STR haplotypes that pointed to a rapid expansion of this haplogroup. Moreover, for the first time, by using both SNP and STR data, we have provided updated estimates of the times-to-the-most-recent-common-ancestor (TMRCA) for E-M183, which evidenced an extremely recent origin of this haplogroup (2,000-3,000 ya). Our results also showed a lack of population structure within the E-M183 branch, which could be explained by the recent and rapid expansion of this haplogroup. In spite of a reduction in STR heterozygosity towards the West, which would point to an origin in the Near East, ancient DNA evidence together with our TMRCA estimates point to a local origin of E-M183 in NW Africa. Funding was provided by the Agencia Estatal de Investigación and Fondo Europeo de Desarollo Regional (FEDER) (grant CGL2016-75389-P), and by Agència de Gestió d’Ajuts Universitaris i de la Recerca (Generalitat de Catalunya) grant 2014 SGR 866. NS is supported by a Formació de personal Investigador (FI) fellowship from Generalitat de Catalunya (FI_B00685)