Angela
Elite member
- Messages
- 21,823
- Reaction score
- 12,329
- Points
- 113
- Ethnic group
- Italian
Here we go again. Can't we just wait for the ancient dna which must surely be on its way?
Oh well, from Xue et al, (including Shai Carmi)
See the following pre-print:
http://biorxiv.org/content/biorxiv/early/2016/07/10/063099.full.pdf
"The Ashkenazi Jewish (AJ) population is important in medical genetics due to its high rate of Mendeliandisorders and other unique genetic characteristics. Ashkenazi Jews have appeared in Europe in the 10thcentury, and their ancestry is thought to involve an admixture of European (EU) and Middle-Eastern(ME) groups. However, both the time and place of admixture in Europe are obscure and subject tointense debate. Here, we attempt to characterize the Ashkenazi admixture history using a largeAshkenazi sample and careful application of new and existing methods. Our main approach is based onlocal ancestry inference, assigning each Ashkenazi genomic segment as EU or ME, and comparing allelefrequencies across EU segments to those of different EU populations. The contribution of each EUsource was also evaluated using GLOBETROTTER and analysis of IBD sharing. The time of admixture wasinferred using multiple tools, relying on statistics such as the distributions of EU segment lengths andthe total EU ancestry per chromosome and the correlation of ancestries along the chromosome. Oursimulations demonstrated that distinguishing EU vs ME ancestry is subject to considerable noise at thesingle segment level, but nevertheless, conclusions could be drawn based on chromosome-widestatistics. The predominant source of EU ancestry in AJ was found to be Southern European (≈60-80%),with the rest being likely Eastern European. The inferred admixture time was ≈35 generations ago, butmultiple lines of evidence suggests that it represents an average over two or more admixture events,pre- and post-dating the founder event experienced by AJ in late medieval times, with the prebottleneckadmixture event bounded between 25-55 generations ago."
So, around 800 AD? Is the speculation still that they were in Italy at that time? Does that mean they're not "Middle Eastern" at all? That doesn't seem right based on their yDna.
Of course, if it's closer to 50 generations ago we'd be talking about around 200 AD? Southern European converts to Judaism?
Well, I guess I'll be reading it today while I'm waiting in reception rooms.
Oh well, from Xue et al, (including Shai Carmi)
See the following pre-print:
http://biorxiv.org/content/biorxiv/early/2016/07/10/063099.full.pdf
"The Ashkenazi Jewish (AJ) population is important in medical genetics due to its high rate of Mendeliandisorders and other unique genetic characteristics. Ashkenazi Jews have appeared in Europe in the 10thcentury, and their ancestry is thought to involve an admixture of European (EU) and Middle-Eastern(ME) groups. However, both the time and place of admixture in Europe are obscure and subject tointense debate. Here, we attempt to characterize the Ashkenazi admixture history using a largeAshkenazi sample and careful application of new and existing methods. Our main approach is based onlocal ancestry inference, assigning each Ashkenazi genomic segment as EU or ME, and comparing allelefrequencies across EU segments to those of different EU populations. The contribution of each EUsource was also evaluated using GLOBETROTTER and analysis of IBD sharing. The time of admixture wasinferred using multiple tools, relying on statistics such as the distributions of EU segment lengths andthe total EU ancestry per chromosome and the correlation of ancestries along the chromosome. Oursimulations demonstrated that distinguishing EU vs ME ancestry is subject to considerable noise at thesingle segment level, but nevertheless, conclusions could be drawn based on chromosome-widestatistics. The predominant source of EU ancestry in AJ was found to be Southern European (≈60-80%),with the rest being likely Eastern European. The inferred admixture time was ≈35 generations ago, butmultiple lines of evidence suggests that it represents an average over two or more admixture events,pre- and post-dating the founder event experienced by AJ in late medieval times, with the prebottleneckadmixture event bounded between 25-55 generations ago."
So, around 800 AD? Is the speculation still that they were in Italy at that time? Does that mean they're not "Middle Eastern" at all? That doesn't seem right based on their yDna.
Of course, if it's closer to 50 generations ago we'd be talking about around 200 AD? Southern European converts to Judaism?
Well, I guess I'll be reading it today while I'm waiting in reception rooms.