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Israel/Zionism See other Israel/Zionism Articles Title: A substantial prehistoric European ancestry amongst Ashkenazi maternal lineages The origins of Ashkenazi Jews remain highly controversial. Like Judaism, mitochondrial DNA is passed along the maternal line. Its variation in the Ashkenazim is highly distinctive, with four major and numerous minor founders. However, due to their rarity in the general population, these founders have been difficult to trace to a source. Here we show that all four major founders, ~40% of Ashkenazi mtDNA variation, have ancestry in prehistoric Europe, rather than the Near East or Caucasus. Furthermore, most of the remaining minor founders share a similar deep European ancestry. Thus the great majority of Ashkenazi maternal lineages were not brought from the Levant, as commonly supposed, nor recruited in the Caucasus, as sometimes suggested, but assimilated within Europe. These results point to a significant role for the conversion of women in the formation of Ashkenazi communities, and provide the foundation for a detailed reconstruction of Ashkenazi genealogical history.... Discussion The extent to which Ashkenazi Jewry trace their ancestry to the Levant or to Europe is a long-standing question5, which remains highly controversial3,4,6,12,13,14,16,17. Our results, primarily from the detailed analysis of the four major haplogroup K and N1b founders, but corroborated with the remaining Ashkenazi mtDNAs, suggest that most Ashkenazi maternal lineages trace their ancestry to prehistoric Europe. Previous researchers proposed a Levantine origin for the three Ashkenazi K founders from several indirect lines of evidence: shared ancestry with non-Ashkenazi Jews, shared recent ancestry with Mediterranean samples, and their absence from amongst non-Jews2, and this suggestion has been widely accepted4. However, our much more detailed analyses show that two of the major Ashkenazi haplogroup K lineages, K1a1b1a and K2a2a1 have a deep European ancestry, tracing back at least as far as the early and mid-Holocene respectively. They both belong to ancient European clades (K1a1b1 and K2) that include primarily European mtDNAs, to the virtual exclusion of any from the Near East. Despite some uncertainty in its ancestral branching relationships, a European ancestry seems likely for the third founder clade, K1a9. The heavy concentration of Near Eastern haplogroup K lineages within particular, distinct subclades of the tree, and indeed the lack of haplogroup K lineages in Samaritans, who might be expected to have shared an ancestral gene pool with ancient Israelites, both strongly imply that we are unlikely to have missed a hitherto undetected Levantine ‘reservoir’ of haplogroup K variation (Supplementary Note 1). Furthermore, our results suggest that N1b2, for which a Near Eastern ancestry was proposed (with much greater confidence than for K) by Behar et al.2, is more likely to have been assimilated into the ancestors of the Ashkenazi in the north Mediterranean. Finally, our cross-comparison of control-region and mitogenome databases shows that the great majority of the remaining ~60% of Ashkenazi lineages, belonging to haplogroups H, J, T, HV0, U4/U5, I, W and M1 also have a predominantly European ancestry. Overall, it seems that at least 80% of Ashkenazi maternal ancestry is due to the assimilation of mtDNAs indigenous to Europe, most likely through conversion. The phylogenetic nesting patterns suggest that the most frequent of the Ashkenazi mtDNA lineages were assimilated in Western Europe, ~2 ka or slightly earlier. Some in particular, including N1b2, M1a1b, K1a9 and perhaps even the major K1a1b1, point to a north Mediterranean source. It seems likely that the major founders were the result of the earliest and presumably most profound wave of founder effects, from the Mediterranean northwards into central Europe, and that most of the minor founders were assimilated in west/central Europe within the last 1,500 years. The sharing of rarer lineages with Eastern European populations may indicate further assimilation in some cases, but can often be explained by exchange via intermarriage in the reverse direction. The Ashkenazim therefore resemble Jewish communities in Eastern Africa and India, and possibly also others across the Near East, Caucasus and Central Asia, which also carry a substantial fraction of maternal lineages from their ‘host’ communities11,25. Despite widely differing interpretations of autosomal data, these results in fact fit well with genome-wide studies, which imply a significant European component, with particularly close relationships to Italians3,4,6,7. As might be expected from the autosomal picture, Y-chromosome studies generally show the opposite trend to mtDNA (with a predominantly Near Eastern source) with the exception of the large fraction of European ancestry seen in Ashkenazi Levites22. Evidence for haplotype sharing with non-Ashkenazi Jews for each of the three main haplogroup K founders may imply a partial common ancestry in Mediterranean Europe for Ashkenazi and Spanish-exile Sephardic Jews, but may also, at least in part, be due to subsequent gene flow, especially into Bulgaria and Turkey, both of which witnessed substantial immigration from Ashkenazi communities in the fourteenth and fifteenth centuries. Gene flow could have been substantial in some cases—ongoing intermarriage is likely when these communities began living in closer proximity after the Spanish exile6. A partial common ancestry for all European Jews—both Ashkenazi and Sephardic—is again strongly supported by the autosomal results3,4. Jewish communities were already spread across the Graeco-Roman and Persian world >2,000 years ago. It is thought that a substantial Jewish community was present in Rome from at least the mid-second century BCE, maintaining links to Jerusalem and numbering 30,000–50,000 by the first half of the first century CE15. By the end of the first millennium CE, Ashkenazi communities were historically visible along the Rhine valley in Germany33. After the wave of expulsions in Western Europe during the fifteenth century, they began to disperse once more, into Eastern Europe33. These analyses suggest that the first major wave of assimilation probably took place in Mediterranean Europe, most likely in the Italian peninsula ~2 ka, with substantial further assimilation of minor founders in west/central Europe. There is less evidence for assimilation in Eastern Europe, and almost none for a source in the North Caucasus/Chuvashia, as would be predicted by the Khazar hypothesis8,9—rather, the results show strong genetic continuities between west and east European Ashkenazi communities10, albeit with gradual clines of frequency of founders between east and west1,2 (Supplementary Note 2). There is surprisingly little evidence for any significant founder event from the Near East. Fewer than 10% of the Ashkenazi mtDNAs can be assigned to a Near Eastern source with any confidence, and these are found at very low frequencies (Fig. 2). The most frequent, belonging to HV1b2, R0a1a and U7, are found at only ~3, 2 and 1% respectively. All are widespread across Ashkenazi communities, and might conceivably be relicts of early Levantine founders, but it seems likely that other more minor Near Eastern lineages are the result of more recent gene flow into the Ashkenazim. The age estimates for the European founders might suggest (very tentatively, given the imprecision with present data) that these ancestral Jewish populations harboring haplogroup K and especially N1b2 may have had an origin in the first millennium BCE, rather than in the wake of the destruction of the Jerusalem Temple in 70 CE. In fact, some scholars have argued from historical evidence that the large-scale expansion of Judaism throughout the Mediterranean in the Hellenistic period was primarily the result of proselytism and mass-conversion, especially amongst women9. We anticipate that a combination of large-scale mitogenome and whole Y-chromosome analysis, complementing full human genome sequencing, will be able to address this question in much finer detail in the near future. Despite the potential of genomic studies, the particular value of full-mitogenome sequencing should be stressed, as some studies dismissed the value of uniparental markers because of the impact of drift in the Ashkenazim6. In fact, the reverse may be the case: autosomal studies may be confounded by drift whereas the fine genealogical resolution of full mitogenomes, given sufficient sampling, can provide a detailed reconstruction of the history of Ashkenazi women. The mtDNA genealogy may even be considered to have particular relevance due to the matrilineal inheritance found in Judaism since at least ~200 CE and possibly several centuries earlier, helping to ‘fix’ incoming lineages from converts within the Ashkenazi community after this time. With sufficient resolution, a detailed genealogical history for every maternal lineage in the Ashkenazim is now within reach; in fact, it should soon be possible to reconstruct the outlines of the entire dispersal history of each community. Poster Comment: Doesn't explain their propensity for criminality. Post Comment Private Reply Ignore Thread
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