Near Eastern origin of Ashkenazi Levite R1a

Over at Nature Communications, Rootsi et al. report on a newly discovered Ashkenazi-specific subclade of R1a, defined by the M582 mutation. They argue that it's a marker of Near Eastern origin, and based on the comprehensive data in their paper, I'd say they're correct. However, it's important to note that this doesn't preclude an ultimate Eastern European or Central Asian source of M582 in the Near East. For instance, an R1a mutation ancestral to M582 might have been introduced by the proto-Iranians from the steppe into what is now Iran during the early Indo-European dispersals. Indeed, that's actually what Figure 1a from the study suggests (phylogenetic tree of R1a below). The paper is open access, but here are a few quotes anyway:

Haplogroup R1a-M582 was only sporadically observed in Europe, the Diaspora residence of Ashkenazi Jews. Notably, it was not identified among 2,149 samples (including 922 R1a-M198) of non-Jews from East Europe, where the Ashkenazi Jewish community flourished in recent centuries (Table 1).

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Within 1,068 West/North European samples (106 R1a-M198), M582 was observed in just one German sample, and among 3,756 Central/South European samples (710 R1a-M198), it was found only in one Hungarian and one Slovakian sample (Table 1).

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Among 3,739 Near Eastern samples (303 R1a-M198), R1a-M582 was identified in various populations, with the highest frequency occurring within Iranians collected from the southeastern Kerman population who self-identified as Persians, northwestern Iranian Azeri and in Cilician Anatolian Kurds, at 2.86%, 2.50% and 2.83%, respectively (Table 1). In contrast, among 2,164 samples from the Caucasus (211 R1a-M198), R1a-M582 was found in just one Nogay sample (Table 1).

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Considering the historical records of Ashkenazi Jews, three potential geographic sources should be considered: the Near East, which was the geographic location for the ancient Hebrews; Europe, which was the residence of the Ashkenazi Jewish Diaspora and the region in which they evolved for nearly two millennia; and the region overlapping with the no longer extant mid-11th Century Khazarian Khaganate, whose ruling class has been suggested to have converted to Judaism [18]. Our data render the latter source highly unlikely since the Khazarian Khaganate overlapped with the Northern Pontic-Caspian steppe and the North Caucasus region, in which just one Nogay sample carried the R1a-M582 haplogroup (Table 1). Furthermore, the Nogays, formerly a powerful Kipchak Turkic-speaking nomadic confederation, are relatively recent inhabitants of the Caucasus, and the STR haplotype of the sole R1a-M582 Nogay sample lies outside of the Levite cluster. Had the Caucasus region been the source for the Ashkenazi modal lineage, we likely would have found R1a-M582 Y-chromosomes in some of its 20 local populations examined in our sample of more than 2,000 Y-chromosomes (Table 1).

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Near Eastern populations are the only populations in which haplogroup R1a-M582 was found at significant frequencies (Table 1). Moreover, the representative samples displayed substantial diversity even within this geographic region (Fig. 1b). Higher frequencies and diversities often suggest lineage autochthony.

Citation...

Rootsi, S. et al. Phylogenetic applications of whole Y-chromosome sequences and the Near Eastern origin of Ashkenazi Levites. Nat. Commun. 4:2928 doi: 10.1038/ncomms3928 (2013).

See also...

The Poltavka outlier