Jewish European ancestry: Khazarian hypothesis

Jewish European ancestry: Khazarian hypothesis Jul 30, 2024 12:53:23 GMT

Quote

Post by Admin on Jul 30, 2024 12:53:23 GMT

The missing link of Jewish European ancestry: contrasting the Rhineland and the Khazarian hypotheses

www.jstor.org/stable/41036207

Abstract
The question of Jewish ancestry has been the subject of controversy for over two centuries and has yet to be resolved. The "Rhineland hypothesis" depicts Eastern European Jews as a "population isolate" that emerged from a small group of German Jews who migrated eastward and expanded rapidly. Alternatively, the "Khazarian hypothesis" suggests that Eastern European Jews descended from the Khazars, an amalgam of Turkic clans that settled the Caucasus in the early centuries CE and converted to Judaism in the 8th century. Mesopotamian and Greco-Roman Jews continuously reinforced the Judaized empire until the 13th century. Following the collapse of their empire, the Judeo-Khazars fled to Eastern Europe. The rise of European Jewry is therefore explained by the contribution of the Judeo-Khazars. Thus far, however, the Khazars' contribution has been estimated only empirically, as the absence of genome-wide data from Caucasus populations precluded testing the Khazarian hypothesis. Recent sequencing of modern Caucasus populations prompted us to revisit the Khazarian hypothesis and compare it with the Rhineland hypothesis. We applied a wide range of population genetic analyses to compare these two hypotheses. Our findings support the Khazarian hypothesis and portray the European Jewish genome as a mosaic of Near Eastern-Caucasus, European, and Semitic ancestries, thereby consolidating previous contradictory reports of Jewish ancestry. We further describe a major difference among Caucasus populations explained by the early presence of Judeans in the Southern and Central Caucasus. Our results have important implications for the demographic forces that shaped the genetic diversity in the Caucasus and for medical studies.

www.ncbi.nlm.nih.gov/pmc/articles/PMC3595026/

Jewish European ancestry: Khazarian hypothesis Aug 6, 2024 3:06:28 GMT

Quote

Post by Admin on Aug 6, 2024 3:06:28 GMT

The Missing Link of Jewish European Ancestry: Contrasting the Rhineland and the Khazarian Hypotheses

Contemporary Eastern European Jews comprise the largest ethno-religious aggregate of modern Jewish communities, accounting for approximately 90% of over 13 million Jews worldwide (Ostrer 2001). Speculated to have emerged from a small Central European founder group and thought to have maintained high endogamy, Eastern European Jews are considered a “population isolate” and invaluable subjects in disease studies (Carmeli 2004), although their ancestry remains debatable between geneticists, historians, and linguists (Wexler 1993; Brook 2006; Sand 2009; Behar et al. 2010). Recently, several large-scale studies have attempted to chart the genetic diversity of Jewish populations by genotyping Eurasian Jewish and non-Jewish populations (Conrad et al. 2006; Kopelman et al. 2009; Behar et al. 2010). Interestingly, some of these studies linked Caucasus populations with Eastern European Jews, at odds with the narrative of a Central European founder group. Because correcting for population structure and using suitable controls are critical in medical studies, it is vital to examine the hypotheses purporting to explain the ancestry of Eastern and Central European Jews. One of the major challenges for any hypothesis is to explain the massive presence of Jews in Eastern Europe, estimated at eight million people at the beginning of the 20th century.

We investigate the genetic structure of European Jews, by applying a wide range of analyses—including three population test, principal component, biogeographical origin, admixture, identity by descent (IBD), allele sharing distance, and uniparental analyses—and test their veracity in light of the two dominant hypotheses depicting either a sole Middle Eastern ancestry or a mixed Middle Eastern–Caucasus–European ancestry to explain the ancestry of Eastern European Jews

The “Rhineland hypothesis” envisions modern European Jews to be the descendents of the Judeans—an assortment of Israelite–Canaanite tribes of Semitic origin (figs. 1 and and2)2) (supplementary note S1, Supplementary Material online). It proposes two mass migratory waves: the first occurred over the 200 years following the Muslim conquest of Palestine (638 CE) and consisted of devoted Judeans who left Muslim Palestine for Europe (Dinur 1961). Whether these migrants joined the existing Judaized Greco–Roman communities is unclear, as is the extent of their contribution to the Southern European gene pool. The second wave occurred at the beginning of the 15th century by a group of 50,000 German Jews who migrated eastward and ushered an apparent hyper-baby-boom era for half a millennium (Atzmon et al. 2010). The Rhineland hypothesis predicts a Middle Eastern ancestry to European Jews and high genetic similarity among European Jews (Ostrer 2001; Atzmon et al. 2010; Behar et al. 2010).

Fig. 1.—
Map of Eurasia. A map of Khazaria and Judah is shown with the state of origin of the studied groups. Eurasian Jewish and non-Jewish populations used in all analyses are shown in square and round bullets, respectively (supplementary table S3, Supplementary Material online). The major migrations that formed Eastern European Jewry according to the Khazarian and Rhineland hypotheses are shown in yellow and brown, respectively.