02-19-2024, 12:03 AM
I remember this being a big thread on the old 'genica, so I thought I would try and revive it! 
Important studies:
https://www.nature.com/articles/ncomms5835 Shai Carmi et al. (2014)
https://journals.plos.org/plosgenetics/a...en.1006644 (Xue et al. 2017)
Both of these studies found that Ashkenazi Jews are a mix of European and Middle Eastern groups, and that some high or late medieval bottleneck cut the population to mere hundreds.
https://www.biorxiv.org/content/10.1101/...805v1.full (Erfurt Study)
https://www.cell.com/current-biology/pdf...1355-0.pdf (English medieval Jews study)
These studies are the first to include samples of medieval Ashkenazi Jews, finding that they had more variation than modern Ashkenazi Jews. The British Jews were a bit more southerly than modern Ashkenazim, while the Erfurt samples had both more and less southerly samples, split into "Erfurt-EU" and "Erfurt-ME".
Other studies:
https://www.pnas.org/doi/epdf/10.1073/pnas.2119281119 (I believe they refer to Ashkenazi as "mixed European" here in graphs? Just has some more info on Jewish population bottleneck)
https://www.biorxiv.org/content/10.1101/467761v1.full (Substructure in Ashkenazi Jews -- Western Ashkenazim are less Northern European, have stronger genetic drift)
Haplogroup Studies:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1380291/ (Behar et al.)
-Ashkenazi mtDNA is highly bottlenecked, "four founding lineages" take up 40% of mtDNA pool
However, studies have disagreed on where these haplogroups originate. Some suggest all 4 are from Europe. Others suggest all 4 and a vast majority of Ashkenazi mtDNA is European in origin
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3806353/
Ashkenazi Y-DNA seems to be less controversially Middle Eastern in origin.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3543766/
Although there are oddities in the Ashkenazi haplogroup record. R1a is extremely common among Levites for some reason, although from what I've heard this R1a likely came from the Middle East (perhaps through Indo-Iranic populations). Although, it's odd that it is an Ashkenazi thing in that case. Aaronites
https://en.wikipedia.org/wiki/Y-chromoso...somal_Levi
There's also evidence of East Asian admixture into Ashkenazi Jews which can't simply be explained by East Asian admixture in Slavs, which allegedly comes from the Silk Road.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4323646/
The Khazar Hypothesis has been quite thoroughly debunked, although I vaguely remember hearing about a book dedicated to Ashkenazi mtDNA and Y-DNA which found some Alanic and Khazarian haplogroups in Ashkenazim. If any of you know what came of this, holler at me.
Anyways, big conversations around Ashkenazi origin include:
-Time and duration of Bottleneck
-Origin of Jewish mtDNA
-Composition of Ashkenazi DNA
-Route Ashkenazim took through Europe (ex: Rhineland Hypothesis)
-Dating of admixture event
-Relationship between Ashkenazi Jews and other Jewish groups
Anyways, I guess I'll get this started just as I remember the thread on Anthrogenica regularly bringing up: That a "50/50 model" for Ashkenazim is anachronistic. Most Ashkenazi Jews were not in parts of Italy with a "Northern Italian" profile that people use to generate this model. It's more likely to me that Ashkenazi Jews descend from an Italkim-like population which underwent its mixing during the Roman period and early medieval period, although may have continued this process gradually into the 2nd millennium AD. Of course, the people in urban Italy at this time were more of a central or southern Italian profile. The aforementioned Erfurt study models Ashkenazim as 70% Southern Italian, and 15% Eastern European and West Asian respectively. Of course, ignoring the West Asian component in Southern Italians. This seems to compliment runs I've had on G25 when comparing Southern Italians and Ashkenazim. although G25 seems to be utterly inconsistent with Mediterranean profiles for me.
Ashkenazim seem to have mixed with Northern Europeans, particularly Eastern Europeans, at a later date. There seems to be some disagreement as to when this happened with the studies. Erfurt suggests it could not have happened after the bottleneck, but earlier studies suggest it must have happened after the bottleneck. I think the most reasonable conclusion is that it happened at the end of the more prolonged bottleneck period suggested in the Erfurt study. This compliments some of the Erfurt samples, who are within this period, having quite substantial Eastern European DNA, while others do not.
But, I would appreciate more input. Especially from people more familiar with Jewish history.
Also, I know that recent world events have made this topic a bit itchy. Please keep all political punditry or motivated arguments over who is indigenous to where out of it.
Important studies:
https://www.nature.com/articles/ncomms5835 Shai Carmi et al. (2014)
https://journals.plos.org/plosgenetics/a...en.1006644 (Xue et al. 2017)
Both of these studies found that Ashkenazi Jews are a mix of European and Middle Eastern groups, and that some high or late medieval bottleneck cut the population to mere hundreds.
https://www.biorxiv.org/content/10.1101/...805v1.full (Erfurt Study)
https://www.cell.com/current-biology/pdf...1355-0.pdf (English medieval Jews study)
These studies are the first to include samples of medieval Ashkenazi Jews, finding that they had more variation than modern Ashkenazi Jews. The British Jews were a bit more southerly than modern Ashkenazim, while the Erfurt samples had both more and less southerly samples, split into "Erfurt-EU" and "Erfurt-ME".
Other studies:
https://www.pnas.org/doi/epdf/10.1073/pnas.2119281119 (I believe they refer to Ashkenazi as "mixed European" here in graphs? Just has some more info on Jewish population bottleneck)
https://www.biorxiv.org/content/10.1101/467761v1.full (Substructure in Ashkenazi Jews -- Western Ashkenazim are less Northern European, have stronger genetic drift)
Haplogroup Studies:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1380291/ (Behar et al.)
-Ashkenazi mtDNA is highly bottlenecked, "four founding lineages" take up 40% of mtDNA pool
However, studies have disagreed on where these haplogroups originate. Some suggest all 4 are from Europe. Others suggest all 4 and a vast majority of Ashkenazi mtDNA is European in origin
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3806353/
Ashkenazi Y-DNA seems to be less controversially Middle Eastern in origin.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3543766/
Although there are oddities in the Ashkenazi haplogroup record. R1a is extremely common among Levites for some reason, although from what I've heard this R1a likely came from the Middle East (perhaps through Indo-Iranic populations). Although, it's odd that it is an Ashkenazi thing in that case. Aaronites
https://en.wikipedia.org/wiki/Y-chromoso...somal_Levi
There's also evidence of East Asian admixture into Ashkenazi Jews which can't simply be explained by East Asian admixture in Slavs, which allegedly comes from the Silk Road.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4323646/
The Khazar Hypothesis has been quite thoroughly debunked, although I vaguely remember hearing about a book dedicated to Ashkenazi mtDNA and Y-DNA which found some Alanic and Khazarian haplogroups in Ashkenazim. If any of you know what came of this, holler at me.
Anyways, big conversations around Ashkenazi origin include:
-Time and duration of Bottleneck
-Origin of Jewish mtDNA
-Composition of Ashkenazi DNA
-Route Ashkenazim took through Europe (ex: Rhineland Hypothesis)
-Dating of admixture event
-Relationship between Ashkenazi Jews and other Jewish groups
Anyways, I guess I'll get this started just as I remember the thread on Anthrogenica regularly bringing up: That a "50/50 model" for Ashkenazim is anachronistic. Most Ashkenazi Jews were not in parts of Italy with a "Northern Italian" profile that people use to generate this model. It's more likely to me that Ashkenazi Jews descend from an Italkim-like population which underwent its mixing during the Roman period and early medieval period, although may have continued this process gradually into the 2nd millennium AD. Of course, the people in urban Italy at this time were more of a central or southern Italian profile. The aforementioned Erfurt study models Ashkenazim as 70% Southern Italian, and 15% Eastern European and West Asian respectively. Of course, ignoring the West Asian component in Southern Italians. This seems to compliment runs I've had on G25 when comparing Southern Italians and Ashkenazim. although G25 seems to be utterly inconsistent with Mediterranean profiles for me.
Ashkenazim seem to have mixed with Northern Europeans, particularly Eastern Europeans, at a later date. There seems to be some disagreement as to when this happened with the studies. Erfurt suggests it could not have happened after the bottleneck, but earlier studies suggest it must have happened after the bottleneck. I think the most reasonable conclusion is that it happened at the end of the more prolonged bottleneck period suggested in the Erfurt study. This compliments some of the Erfurt samples, who are within this period, having quite substantial Eastern European DNA, while others do not.
But, I would appreciate more input. Especially from people more familiar with Jewish history.
Also, I know that recent world events have made this topic a bit itchy. Please keep all political punditry or motivated arguments over who is indigenous to where out of it.