Hi- Some work of mine just got published- I thought some others might be interested. The paper is called Sephardic Signature in Haplogroup T Mitochondrial DNA
Here's the link to the article and I've enclosed a general summary below.
http://www.nature.com/ejhg/journal/vaop/ncurrent/full/ejhg2011200a.html
Most libraries have a subscription (Open Access was too expensive!) but I can probably send a pdf if anyone's library does not have access.
Here's the summary:
General Summary of:
Bedford, F.L. Sephardic Signature in Haplogroup T Mitochondrial DNA, European Journal of Human Genetics. Advance online publication November 23, 2011
I discovered that there are a couple of variants/mutations in mitochondrial DNA that appear to be found only in people who are Sephardic or have a high suspicion of Sephardic ancestry. Recall that mitochondrial DNA is inherited only from one's mother, so it's become an indispensable tool for tracing maternal lineage back hundreds, sometimes thousands, of years. The people with high suspicion of Sephardic ancestry includes
individuals from regions of northern Mexico and southwest USA that are known for crypt-Jewish settlement. These are very rare genetic variants, so the majority of Sephardim will NOT have them.
Because the variant is so rare, I also looked at the genetic group from which these variants derive. Here I found that while this bigger genetic group is widespread geographically, it is more prevalent in Saudi Arabia, Egypt, and Italy than it is in Spain. In addition, Sephardim from Turkey and Bulgaria show this genetic pattern in numbers that are closer to these three regions than to Spain. This suggests that while Spain hosted
Sephardim for 1500 years, the genetics are closer to regions in the Middle East and Italy than to host Spain. The geographic distribution suggested a migration path from the Middle East with a stop in Italy and on to Iberia and then into Western Europe. Since this migration path characterizes both Jewish and non-Jewish groups at various points in history, the work at present cannot prove that the Sephardic signature DNA is original
Jewish DNA from exilers seeking asylum following destruction of the first temples by Romans or Babylonians. It is nonetheless exciting to tie DNA with a known historical migration path that is likely close to 2000 or more years old, something that is not always possible with DNA analyses.
The work also theoretically briefly considerers Sephardim and Ashkenazim on the so called issue of "founder effects" which address how many distinct individuals - in this case mothers- were responsible for the present day population in a community. A large or pronounced founder effect is said to occur if very few individuals were responsible for a
large proportion of the current DNA in that population. It has been reported that Ashkenazim have a more pronounced founder effect than Sephardim. This certainly would make sense historically since there were more Sephardim than Ashkenazim until recently and Sephardim brought with them to new locations all their genetic variability when exiled from Iberia in the late 15th century. However, current comparisons erroneously
combine all Ashkenazi communities together while keeping Sephardic communities separate - a comparison of apples and oranges. The bottom line is that at present this issue of founder effects has not been resolved. We do currently know limited things, such as descendents of the Sephardic community of Turkey have a less pronounced founder effect and greater genetic variability than descendents of the Ashkenazi community of Poland.
Finally, another part of the data analyzed gets technical. The couple of rare variants in DNA mentioned above come from a part of the mitochondrial DNA known as the "control region". This is the part that accumulates surviving mutations in the greatest numbers because these control regions do not typically code for anything important. Control regions have been tested the most, with at least 250,000 individuals tested worldwide that are available for searching, as was done in the present research. But recently, testing of the remaining regions of the mitochondrial DNA, from the "coding regions" is becoming more frequent. The coding regions do code important information and can have medical as well as other implications.
Analysis of one Sephardic sequence from Salonica Turkey/Greece with the Sephardic signature of interest (based on control region mutations) was found to have a couple of further variants in the coding regions. Unlike the variants from control regions which were not remarked on before, these coding region variants are shared with others already in the scientific literature (and come from individuals who do not have the Sephardic
control region mutations). These coding region mutations will eventually provide an important link of at least some of Sephardim with the rest of the world. It is very premature to speculate, but I suspect the origins of this broader more prevalent and widespread group may actually also be Jewish, even in those who neither know nor suspect this origin, but it will take a lot of work to prove this. If nothing else, it shows that the Sephardic signature individuals share a common maternal ancestor, anywhere
from 500 to 16,000 years ago, with these other individuals.
For those interested in details, the defining control region mutations for the Sephardic signature are the presence of both 16114T and 16192T in mitochondrial subhaplogroup T2e.
There is much to be done. Availability of both my time and other factors will determine whether or not I am able to advance the work myself.
I hope everyone will consider having their DNA tested. Think twice though about uploading your raw data in exchange for a "free analysis" of your DNA.
Felice
bedford@u.arizona.edu
On a beau connaître des destins de Juifs célèbres contraints à l'exil par la montée du nazisme, on a beau savoir l'existence de camps de transit ou d'internement des étrangers sur le sol français, avoir des visions de paquebots bondés en partance quand ils partaient - pour l'Afrique du Nord ou l'Amérique, on n'imaginerait sans doute pas l'immense chaos européen de ces foules déplacées sans l'impressionnante saga historique des Autrichiens Axel Corti (réalisateur, décédé en 1993) et Georg Stefan Troller (scénariste), Welcome in Vienna.
