Ashkenazi Jewish Origins Thread

[Rodoorn]

I think the Roman communities along the Rhine might be responsible for a lot of (Eastern) Mediterranean lineages in our lands; if I remember correctly, there will be more results from the (Late) Roman/Merovingian period from the NRW area soon.

Just as think exercise.

I have asked Chat GPT:

Which change in numbers is bigger? On the one hand  the change in numbers when a solitary Y-DNA  branch flows in 1000 AD into a population that this Y-DNA branch still survives today in this population? On the other hand the change that someone is hit  by a thunder and wins the postcode lottery during a lifetime in the Netherlands?

To determine which change in numbers is bigger between the survival of a solitary Y-DNA branch from 1000 AD to today and the probability of being hit by thunder and winning the postcode lottery during a lifetime in the Netherlands, we need to examine the probabilities involved in both scenarios.

### Scenario 1: Y-DNA Branch Survival from 1000 AD

1. **Introduction and Survival of Y-DNA Branch**:
  - A solitary Y-DNA branch enters a population in 1000 AD.
  - Assuming the population size was around 1,000,000 people in 1000 AD.

2. **Modern Population**:
  - Considering the modern Netherlands with approximately 17 million people.

3. **Generations**:
  - From 1000 AD to 2024 AD is approximately 1024 years.
  - Assuming 25 years per generation, this gives us about 41 generations.

4. **Calculating Survival**:
  - Assuming a conservative probability of 0.5 for each generation (each man has a 50% chance of having at least one son who survives), the probability of survival over 41 generations is \(0.5^{41} \approx 4.55 \times 10^{-13}\).
  - Real-world survival rates might be higher due to multiple descendants and interconnected populations.

### Scenario 2: Hit by Thunder and Winning Postcode Lottery

1. **Probability of Being Hit by Thunder**:
  - The annual chance of being struck by lightning in the Netherlands is roughly 1 in 1,000,000.
  - Over an average 80-year lifetime, this is about \(80 \times 1/1,000,000 = 1/12,500\).

2. **Probability of Winning the Postcode Lottery**:
  - The chance of winning the postcode lottery is around 1 in 10,000,000 for major prizes.

3. **Combined Probability**:
  - The combined probability of both events happening in a lifetime is the product of the two probabilities: \( \frac{1}{12,500} \times \frac{1}{10,000,000} = 8 \times 10^{-12} \).

### Comparison:

- **Survival of Y-DNA**:
  - The probability of a Y-DNA line surviving over 41 generations is approximately \(4.55 \times 10^{-13}\).

- **Thunder and Lottery**:
  - The probability of being struck by lightning and winning the postcode lottery is \(8 \times 10^{-12}\).

**Conclusion**:
The change in numbers is bigger in the scenario of someone being hit by thunder and winning the postcode lottery during a lifetime in the Netherlands. The probability of this combined event, while very small, is still larger than the probability of a solitary Y-DNA branch surviving from 1000 AD to the present day. The Y-DNA survival probability is \(4.55 \times 10^{-13}\), which is smaller than the \(8 \times 10^{-12}\) probability of the combined thunder and lottery event.

[Pylsteen]

I'll elaborate later today, there are some interesting insights from a.o. our friend Penninx.

[Rodoorn]

I'll elaborate later today, there are some interesting insights from a.o. our friend Penninx.

There are a few things to consider (I correspond on practically daily basis with Penninx we have made a website together).

- E-V22's rise 8000 ybp> went most probably together with the rise of the (semi) nomadic pastoralists and the semitic language from the 'heartland' in Southern Levant. That's differentiated from how Penninx and I hitherto considered it (see https://e-v22.net);

- mark that in the Erfurt paper and also by people like Khan is stressed that the modern Ashkenazim don't fully equal the Jewish in NW Europe in the middle ages and most probably not fully the Frisian Jews between 1600-1700. Mark that in 1670 they got a cemetery before that no sedentary Jews in Leeuwarden. Khan: 'a lot of the medieval Jewish communities simply went extinct.' And I would add that this could also be the case with some E-V22 lines like E-L1401 which has a clear semitic base.

- the spread in NW Europe - and even more in Friesland!- of E-V22/E-L1401 is complete solitary, white ravens.  I was previous indeed convinced that the Roman empire moved some semitic E-V22 to the Rhineland (Aachen, Köln, Mainz etc) and from there to Friesland, nevertheless when this happened during the middle ages the survival rate unto today is incredible small (in fact non existent).

- we have to consider that seen the autosomal of my father there is a presence beyond noise c.q. the 1% Druze in overall autosomal DNA. The Druze are according to Davidski when he wrote about the Erfurt paper most comparable with the Near East/ Levant Jews.  Davidski: "the spreadsheet also shows that the so called Middle Eastern cluster is modal (that is, it peaks in) the Druze."  Beneath the 1% Druze in total of chromosomes, there is a clear presence in especially some chromosomes (3,4, and more), so  that can't be seen as noise or some kind of Frisian average (no way!).

- this equals about an entre in my tree about 7 generations ago, that's end 17 th century, Wartena close to Leeuwarden in a Frisian skipper family which belonged to a Roman-Catholic minority. Mark that an influx of a solitary Y-DNA 7 generations ago and the survival unto today is already small but not fare fetched.

- last but not least the social context: a Semitic/Jewish line infused in a non-Jewish (in casu Roman Catholic) Frisian family was from both sides taboo. They didn't met, they didn't mix (norm along the Roman-Catholics and the Jews), but in Leeuwarden about 7 generations ago from my father they used the same worship house known as the Ammelander Pijp. That didn't change their norms but when they shared the same room they couldn't ignore each other. This opens the opportunity of: illegitimate child, adoption, foundling etc. Of course this was covered up. Nevertheles this was a real 'social opportunity', that was in that sense quite unique!



So no proof, no definite story, but 'let go of the idea of a Jewish paternal origin':not yet. Because with all the complications this is- also from the numeric, genetic side- imho the most real option. Of course when there is a better scenario be my guest! And yes I'm argumentative, not easy satisfied etc etc  but since the days of Baruch Spinoza this is also a nice tradition isn't it?

[Rodoorn]

Deleted, have to examen it more.

[Pylsteen]

I wanted to comment on your last message, but I see you've deleted it; in any case, the family of Uri halevi (who is the direct paternal ancestor of rabbi Jacobs, and from whom I descend as well) is certainly Ashkenazi. He was asked by the emerging Portugese community in Amsterdam to teach them the beginnings of the jewish rites; imagine, the Portugese were raised for already 4 generations in a catholic environment, they didn't remember much about judaism except for very general things, so they needed someone who knew about the rites. Later rabbi halevi went back to Emden/Friesland.

The rest I will respond on later today! First enjoy the nice pentecost weather.

[Rodoorn]

I wanted to comment on your last message, but I see you've deleted it; in any case, the family of Uri halevi (who is the direct paternal ancestor of rabbi Jacobs, and from whom I descend as well) is certainly Ashkenazi. He was asked by the emerging Portugese community in Amsterdam to teach them the beginnings of the jewish rites; imagine, the Portugese were raised for already 4 generations in a catholic environment, they didn't remember much about judaism except for very general things, so they needed someone who knew about the rites. Later rabbi halevi went back to Emden/Friesland.

The rest I will respond on later today! First enjoy the nice pentecost weather.

I deleted it because I want to examen it more, not only because of a few notes. When he played such a role in Amsterdam, this could also mean that he had to teach the Leeuwarder Jews about Judaism.....to some conversos.

[Pylsteen]

Ok, first a post about specifically the Sephardic migrations out on top of my head... as you know it is close to my heart since my jewish gg-mother was a quarter Portugese-jewish.

So, what may Sephardic migrations have meant for the Ashkenazi populations? First, it is important IMO to distinguish between two groups of Sephardic migrants:

1. The older group, leaving Iberia already in 1492. This group remained religiously jewish, and migrated mainly to Portugal, North Africa, places in Italy, the Ottoman Empire and central Europe; one example may have been the family of my ancestor Nathan Spanier (an Ashkenazi from lower Saxony, but note the surname). In both Poland and Germany these are assumed to have been absorbed by the larger Ashkenazi populations.
   
2. The conversos (new christians). Those that remained in Iberia and converted to catholicism after 1492, during the early 16th century also including those jews that had fled to Portugal. During the 16th century, a diaspora started, caused by IMO both trading opportunities and the rise of the inquisition, first in places such as Antwerp, from the late 1590s Amsterdam and Hamburg, and also in typical places such as Venice, Livorno, Bordeaux, Brazil, and later London communities emerged. They tended to be involved in trade over sea, such as with Africa and the Americas (especially Brazil and the Caribbean), in which they utilized their large network of relatives. Often they had family and friends still in Portugal and in other places of the diaspora. When they had come to Antwerp, Amsterdam and Hamburg, they were initially not accepted as jews, but they were as Portugese catholics. In the Dutch Republic, they were welcome in Amsterdam, Middelburg (temporarily), The Hague and Rotterdam. Smaller communities were present in Naarden and Maarssen. Outside of these places, they were generally not found during the 17th and 18th century: why leave the large cities where your network was? Only singletons may have left. There is no clear evidence for conversos in Leeuwarden during the 17th century; IIRC, there were one or two families in Emden. The conversos tended to be (obsessively) proud of their Iberian heritage. Ashkenazim were seen as foreign people, speaking a different language (Yiddish) and had a lower prestige. In Amsterdam, the Portugese were the landlords, Ashkenazim the tenants. Marriages between both groups were frowned upon and were very rare before the late 18th century; in the cases that they did occur, the groom was often Italian/Venetian rather than Iberian jewish. From the late 18th century onwards, mixed marriages became more common due to the impoverishment of many Sephardic families and emancipation of the Ashkenazim. Besides that, there exist stories during the 17th and 18th century of Portugese men who had fathered children by their Ashkenazi maids. A small stream of conversos also went to Poland.
   

Long story short: when speaking about the Sephardim, the first migration of Sephardim during the 16th century to Ashkenazi lands IMO were largely absorbed by the local Ashkenazi communities; it is not clear to me how large this group was and whether there are still paternal lineages from them left among the current-day Ashkenazim. The conversos of the 17th century however stuck more together in the larger cities and tended to keep a larger social distance from the Ashkenazim; their genetic influence on the Ashkenazim during the 17th and 18th century was very small IMO.

Next post more on the larger context.

[Pylsteen]

My post from earlier in this thread is pretty much how I think about the origins of the Ashkenazim, summarized:

1. Proto-Ashkenazim resulting from a bottleneck of Western Jews, likely between ca. 600-900 AD (probably Carolingian context)
   
2. Spread of post-bottleneck Ashkenazim among France, Germany, England, Central+Eastern Europe where they heavily mixed with mostly Slavic women. In the meantime, Jews from IMO mostly Italy, but other places such as Iberia and the Byzantine empire as well migrated to Germany. This all created several subclusters of Ashkenazim.
   
3. During the entire middle ages periods of expulsion and intermarriage led again to a fairly homogenous Ashkenazi population at the beginning of the modern era, with a cline from Germany in the west to Russia in the east. Some input from Sephardic (and Greek) jews in the early modern period, etc. The entire story of all expansions and expulsions is too extensive to write down here.
   

On the Y-DNA and the ancient samples we have

Probably interesting for your quest is the model Penninx ran to explain the current-day distribution of Y-dna frequencies among Ashkenazim. Especially his model 4 seems in line with what we see. In this model, there are 75 surviving lineages from 400 founder men, arriving during several periods in time. Following this model, I would say there may have been roughly 300 lineages that entered the Ashkenazi population from its beginning until the later middle ages, from both jewish fathers and European men, that have disappeared from the modern-day Ashkenazim. I imagine that several of these lineages are still present among other present-day jewish groups, and perhaps even among non-jewish groups (there's the possibility you are interested in - the only things I am cautious about are the social circumstances, indeed from both sides a conversion or mixed relationship was very much taboo but also the total lack of understanding of your lineage from 3500 BC to the 1600s).

That during the middle ages jews from other communities enriched the early Ashkenazi gene pool is IMO quite good visible from all the Ashkenazi Cohen-lineages below J1-Z18271: several of the Ashkenazi-specific branches have high medieval TMRCA's rather than "Carolingian", although of course the age of its entrance before the TMRCA cannot exactly be determined.

Can the ancient samples tell us something?

Among the Erfurt samples we have the following Y-DNA results:

• Erfurt-ME ("Rhinelandic" IMO): 2x J2a-L556, 1x R1b-Y19847 (both typically Ashkenazi)
  
• Erfurt-EU ("Kna'anic" IMO): 1x J1-CTS4459 (IMO likely downstream J-ZS2616), 1x T-Y105938, 1x R1b-L4, 1x R1b-L584 (IMO possibly downstream R-FGC36759 or R-FGC14602), 1x R1b-Y4364 (IMO possibly downstream R-Y19847), 1x E1b-CTS10298 (can be downstream E1b-Y36800 or E1b-PF6769 (incl. Einstein lineage) but also Sephardic E1b-S16614 (incl. Curiel lineage), largely Ashkenazic with some space for interpretation.
  

Besides the Erfurt samples, we also have the earlier 12th century samples from Chapelfield (England). These English jews must have been descended from the French jews that William the Conqueror brought to England and are IMO likely similar to the Proto-Ashkenazim and Rhinelandic jews. They share the bottleneck with the Erfurt and modern Ashkenazim, they lack the Slavic admixture found in Erfurt-EU samples, as expected.

Y-DNA lineages found among them:

• 1x E1b-PF6769, 1x J1-FT174623 (found in modern-day Sephardim, not in Ashkenazim, such as its larger sister lineages below J1-ZS4297), 1x T-Y125276 (seems present among Ashkenazim these days, but seems more prolific in Sephardim).
  

among the medieval samples we see indeed the lineages as found in modern Ashkenazim, but also (especially in Chapelfield) lineages that are more common in Sephardim today and seem to reflect a larger diversity among medieval Ashkenazi Y-DNA that was lost later on.

[Dewsloth]

Ok, first a post about specifically the Sephardic migrations out on top of my head... as you know it is close to my heart since my jewish gg-mother was a quarter Portugese-jewish.

So, what may Sephardic migrations have meant for the Ashkenazi populations? First, it is important IMO to distinguish between two groups of Sephardic migrants:

1. The older group, leaving Iberia already in 1492. This group remained religiously jewish, and migrated mainly to Portugal, North Africa, places in Italy, the Ottoman Empire and central Europe; one example may have been the family of my ancestor Nathan Spanier (an Ashkenazi from lower Saxony, but note the surname). In both Poland and Germany these are assumed to have been absorbed by the larger Ashkenazi populations.
   
2. The conversos (new christians). Those that remained in Iberia and converted to catholicism after 1492, during the early 16th century also including those jews that had fled to Portugal. During the 16th century, a diaspora started, caused by IMO both trading opportunities and the rise of the inquisition, first in places such as Antwerp, from the late 1590s Amsterdam and Hamburg, and also in typical places such as Venice, Livorno, Bordeaux, Brazil, and later London communities emerged. They tended to be involved in trade over sea, such as with Africa and the Americas (especially Brazil and the Caribbean), in which they utilized their large network of relatives. Often they had family and friends still in Portugal and in other places of the diaspora. When they had come to Antwerp, Amsterdam and Hamburg, they were initially not accepted as jews, but they were as Portugese catholics. In the Dutch Republic, they were welcome in Amsterdam, Middelburg (temporarily), The Hague and Rotterdam. Smaller communities were present in Naarden and Maarssen. Outside of these places, they were generally not found during the 17th and 18th century: why leave the large cities where your network was? Only singletons may have left. There is no clear evidence for conversos in Leeuwarden during the 17th century; IIRC, there were one or two families in Emden. The conversos tended to be (obsessively) proud of their Iberian heritage. Ashkenazim were seen as foreign people, speaking a different language (Yiddish) and had a lower prestige. In Amsterdam, the Portugese were the landlords, Ashkenazim the tenants. Marriages between both groups were frowned upon and were very rare before the late 18th century; in the cases that they did occur, the groom was often Italian/Venetian rather than Iberian jewish. From the late 18th century onwards, mixed marriages became more common due to the impoverishment of many Sephardic families and emancipation of the Ashkenazim. Besides that, there exist stories during the 17th and 18th century of Portugese men who had fathered children by their Ashkenazi maids. A small stream of conversos also went to Poland.
   

Long story short: when speaking about the Sephardim, the first migration of Sephardim during the 16th century to Ashkenazi lands IMO were largely absorbed by the local Ashkenazi communities; it is not clear to me how large this group was and whether there are still paternal lineages from them left among the current-day Ashkenazim. The conversos of the 17th century however stuck more together in the larger cities and tended to keep a larger social distance from the Ashkenazim; their genetic influence on the Ashkenazim during the 17th and 18th century was very small IMO.

Next post more on the larger context.

It's funny that my last fully (autosomally) Rhine Ashkenazi ancestor, who was baptised Catholic at birth, grew up in Germany to be, besides a paper magnate, a "royal Spanish and Portuguese consul who ran a general agency for emigrants to America via Le Havre" -- almost like they still had solid connections with [Converso? Sephardic?] communities there:
https://de.wikipedia.org/wiki/Alois_Dess...n_Dessauer

[Rodoorn]

@Pylsteen, thanks for the exposé, nice read!

Nevertheless it doesn't react on my quest and considerations.

As E-V22 has most probably a connection with the occurrence of semi nomadic pastoralism and the spread of proto-Semitic in the  Southern-Levant (and beyond) 6000 BCE. My E-L1401 is branched off 3500 BCE, so at the start of the Bronze Age in the Southern Levant, that most probably is connected to one of the Canaanite groups as described in:

The Genomic History of the Bronze Age Southern Levant

Judaism is from about 2000 BC so it's quite possible that people with E-L1401 were from the early days part of it.

In the case of E-L1401 we see this is a fully but really a fully solitary line in Friesland, in North Dutch, in Dutch in North West Europeans even in all Europeans

For such solitary lines it is an understatement that it's more likely that it infused in the last centuries than in the middle ages (see for the chances above). The simple fact is that towards Friesland there is since about 1650 no other known semitic spread than that of the Jews! Simple but true. (By the way neither before

Chatgpt

"Scenario: Genetic Drift and Small Population

Initial migrant group: 1 male with the Y-DNA line.
The population remains small and isolated.
Due to genetic drift, after several generations, there's a high chance of losing the Y-DNA line purely by chance if the male descendants do not survive or do not have male offspring."

This was  imo with regard to the Frisian Jews AND with E-L1401 the case.

And true this would be a line that is not restricted to Jewish E-V22 "usual suspects", in fact @Riverman gives a perfect prescription of it:

"What I wonder about is how common actually rare yDNA-subclades among Ashkenazi Jews are, which have a deeper Jewish history, to put it that way. Like going back to the Medieval period and earlier.
Because most Ashkenazi lineages are both widespread and well-tested, due to Medieval and later founder events, as well as Ashkenazi Jews being more willing and able to test than many other populations from around the world. But are there actually proven, historically Jewish lineages which are more rare? Its hard to prove they are Jewish without ancient DNA and when there is no more than 1 Jewish tester.
I tried to find such rare lineages with say less than 3 modern testers which are clearly Jewish, but with no luck so far. All proven Jewish subclades have, if consulting FTDNA and YFull, got more testers and experienced a founder event. That's why I'm asking whether there are any known rare ones at all.

The criteria would be:
- Less than 4, but more than 1 tester with FTDNA and YFull being combined
- A TMRCA pointing to an old branching event from within the Jewish population, not a recent (after 1700) proselyte, NPE or other such scenarios."

E-L1401 could be such a line....there are more such E-V22 beneath E-PH2818 (E-L1401 is branched off), like in the Jewish E project  FTDNA dataset: "95660 Elkayam / Kaim: Sefarad, Spain, Morocco, Israel Morocco E-PH2818".




Hidden in between your own suggestion?

"Besides the Rhineland and Kna'anim groups there was likely more substructure we dont know of yet. In any case, both groups contributed to the modern Ashkenazim in different proportions (a cline is still seen from German jews to Russian jews). Of course there are many complex details due to the many expulsions. Additionally, Sephardim, perhaps Italkim and jews from the Levant/Mesopotamia also came to Central/Eastern Europe."

[Rodoorn]

@Pylsteen "Outside of these places, they were generally not found during the 17th and 18th century: why leave the large cities where your network was?" You underestimate the vivid Jewish life "in the mediene"!

You already mentioned Jacob Philips Josephs "(Jacob de Jode)"  and the role he (and his family) played from Emden towards the early Sephardim community in Amsterdam, he did also for Leeuwarden.

They were attracted towards the very commercial economy- based on a very advanced agriculture- in the Frisian (and Groningen) towns. Traders, butchers, bankers were needed! There are very early mentioning of Jews in Appingedam (official in 1536 with Joest Musken from Prague), Winschoten, Nieuweschans, Warffum Winsum and of course Groningen. in Friesland: besides Leeuwarden (at that time seat of the Stadhouder of Orange)  there were communities in Bolsward, Gorredijk, Sneek, Harlingen, Franeker, Lemmer. In little Zwaagwesteinde Solomon Levy caused even a revolt in 1789 (people still remember him): the Kollummer oproer.

At the end of the 18th century there was- because of a flourishing economy  "in the mediene"  a real attraction of Jews from the cities in the west toward "the province".

In Leeuwarden there were 354 Jews in 1796 and 632 in 1809. The economy flourished in the North until 1880. At that time the amount of Jews was at his hight. There were about 2235 Jews in Friesland in 1879. After 1880 (crisis in the rural economy) there was a concentration of Jews towards the West.

And after the holocaust only 17 Jews returned to Friesland and the total amount was only 150 (in 1945).....

Nevertheless Jews were very present in the little towns in the North, I was grown up near Winschoten which contained before ww2 relative the most Jewish citizens. It was called little Amsterdam or Sodom. It coined even the language, which got loans from Jiddisch. When darks clouds appeared my grandfather said, "doar komt maaium/mekaaium aan", kids were "grommen". This is from memory there will be lots more.

Anyhow the Jewish life was vivid in the mediene Pylsteen!

[Pylsteen]

Nevertheless Jews were very present in the little towns in the North, I was grown up near Winschoten which contained before ww2 relative the most Jewish citizens. It was called little Amsterdam or Sodom. It coined even the language, which got loans from Jiddisch. When darks clouds appeared my grandfather said, "doar komt maaium/mekaaium aan", kids were "grommen". This is from memory there will be lots more.

Anyhow the Jewish life was vivid in the mediene Pylsteen!

I know, but these were in principal Ashkenazi (not conversos) communities; as told above the dynamics for the conversos networks were different.

As for your lineage - the question remains, when between 3500 BC and the 1600s did it turn from a Levantine to a NW European lineage? Did it do so in 1 step? Were more steps involved?

[Rodoorn]

Jewish beneath E-V22, E-PH2818:



Israel Y-tree:
https://www.theytree.com/?snp=PH2818

[Rodoorn]

Nevertheless Jews were very present in the little towns in the North, I was grown up near Winschoten which contained before ww2 relative the most Jewish citizens. It was called little Amsterdam or Sodom. It coined even the language, which got loans from Jiddisch. When darks clouds appeared my grandfather said, "doar komt maaium/mekaaium aan", kids were "grommen". This is from memory there will be lots more.

Anyhow the Jewish life was vivid in the mediene Pylsteen!

I know, but these were in principal Ashkenazi (not conversos) communities; as told above the dynamics for the conversos networks were different.

As for your lineage - the question remains, when between 3500 BC and the 1600s did it turn from a Levantine to a NW European lineage? Did it do so in 1 step? Were more steps involved?

All I can think of now that it's most likely connected with Sephardim (they had E-V22 beneath-E-PH2818, E-L1401 is also derived from E-PH2818).

May be:
https://en.wikipedia.org/wiki/Eastern_Se...rs%20later.

The Sephardim had a direct connection with the Levant, were even partly derived from the Near Eastern Jews. If there was a network that was able to "transfer"  E-L1401 in the 17th century towards the Netherlands (Friesland) it was this network.

[Piquerobi]

An interesting article by the Israeli newspaper Haaretz on the Erfurt study and the origins of the Ashkenazi Jews:

"The origins of Ashkenazi Jews are shrouded in mystery. We know that the first Ashkenazi communities emerged in the Rhineland at the height of the Middle Ages, around the 10th century. But how and when Jews first reached the Rhine Valley, developing the distinct, rich culture that would eventually spread across Europe and much of the world , is not clear.

The origins of Ashkenazim have also been of interest to geneticists because they carry a disproportionate amount of gene mutations, some of which can cause chronic or fatal diseases.

Now a DNA study sheds new light on the roots of the Ashkenazi population and its early history, which turns out to have been more complex than we thought, says Prof. Shai Carmi, a geneticist from the Hebrew University in Jerusalem who led the research.

Carmi, his doctoral student Shamam Waldman, and an international team of researchers were able to extract DNA from the teeth of 14th century skeletons buried in the Jewish cemetery of Erfurt, in central Germany.

The study in itself is a rare feat. In the last decades, ancient DNA studies have been legion and revealed much information about the origins and movement of human populations in the past. But because disturbing human remains is a big no-no under Jewish religious law, it is not often that researchers get to extract DNA from the ancient bones of members of the tribe.

In fact, the new study, published Wednesday in the journal Cell, is one of the first two efforts to sequence ancient DNA from the remains of Ashkenazi Jews. In another such study, published in August, researchers extracted DNA from 17 bodies found buried in a medieval well in Norwich, only realizing these may have been the Jewish victims of a pogrom when they identified genetic mutations typical of Ashkenazim. In that case, the identification of the bodies as Jewish, while very likely, remains unconfirmed.

For the Erfurt study, there is little doubt of the identity of the subjects, as Carmi and colleagues obtained the DNA of 33 individuals buried in the town’s medieval Jewish cemetery.


Researchers collected 38 teeth from the medieval Jewish cemetery in Erfurt, from which they extracted ancient DNA from 33 individuals.

The Jewish community of Erfurt existed from the late 11th to the mid 15th century, with a short gap following a 1349 pogrom that all but wiped out the entire community.

After expelling the Jews in 1454, the city built a granary on top of their cemetery. Come the year 2013, when the granary was no longer in use, Erfurt converted it into a parking lot, which led to additional construction and an archaeological rescue excavation. Armed with recent rabbinical rulings that allow for ancient DNA research to be conducted on detached teeth, the researchers obtained permission from the local Jewish community to sample the remains, which were later reburied in the town’s 19th century Jewish cemetery.

Radiocarbon showed that the bodies, all but one buried with their feet facing Jerusalem according to Jewish custom, dated to the 14th century, though it is unclear whether they lived before or after the 1349 massacre, one of many perpetrated against European Jews during the Black Death. There were 19 females and 14 males, many of them children, and only one individual showed signs of a violent death: several blows to the head with a sharp object.

An ancient split

The analysis of their genomes showed that at least eight of these Jews carried the same pathogenic gene variants typical of Ashkenazim today, which can cause severe illnesses. These include retinitis pigmentosa, which degrades the retina; Gaucher disease, which causes a dangerous buildup of fatty tissues in organs or bone tissue; Usher syndrome, which causes deafness and blindness, as well as the BRCA1 variant that increases the risk of breast and ovarian cancer.

The prevalence of so many specific mutations among Ashkenazi Jews has long been suggested as a sign that this group went through a bottleneck, or a “founder event.” In other words, for whatever reason – all Ashkenazim today descend from a single tiny group.

“We don’t know the nature of the bottleneck : whether it was a continuous decline over several centuries or a single event where, for example, a small group moved away from the main population, which is a classic founder event,” Carmi says.

The upshot would have been that the members of this small group married within their small group, leading to diminished genetic variation. In extremes, loss of genetic variation and isolation lead to speciation; in the case of Ashkenazim, it meant that even as the population grew, its members shared a lot of genes, including “bad” ones that, when inherited from both parents, cause illness or even death.

Another sign that all Ashkenazim extant today descend from a tiny founding population is the fact that 40 percent of modern Ashkenazim carry the same four sequences of maternally-inherited mitochondrial DNA, meaning they descend from just four ancestral mothers. This was even more pronounced in the Erfurt Jews. More than a third of the individuals in the sample descended from a single woman through their mitochondrial DNA, the researchers report in Cell.

The singular finding of the Erfurt study is that while the DNA of modern Ashkenazim is fairly homogenous, in the Middle Ages this Jewish population could have been divided in two genetically distinct groups. One had greater Middle Eastern and Southern European ancestry and was genetically closer to modern Ashkenazim originating in France and Germany. The second had a similar ancestry mix with an additional genetic component typical of Eastern Europe, Carmi says.

Since both groups shared the typical “founder mutations,” the most likely explanation for this difference is that they both descended from the same small original population, which then split into two. One settled (or remained) in the Rhineland and one headed for Eastern and Central Europe.

Then, at the end of the Middle Ages, in places like Erfurt, the two communities began to mix anew as a result of migrations, and eventually coalesced into today’s homogenous Ashkenazi genome.

While it was known from historical records that Jews from Bohemia, Moravia and Silesia migrated westward into Erfurt at this time, it was not recognized that these two populations had been genetically distinct, Carmi says.

By the way, this Eastern European component should not be seized upon as a way to support the long-discredited “Khazar hypothesis” – that is, the claim that Ashkenazim have no link to the ancestral population of Judah but descend instead from the Khazars, an early medieval kingdom in the Caucasus where part of the population had converted to Judaism.

The Eastern European component found in some of the Erfurt Jews is only a minor fraction of their ancestry, and there were no major direct links to the Caucasus, Carmi tells Haaretz.

The Erfurt study doesn’t dispel all the mysteries surrounding the origins of Ashkenazim, but it does give us some hints. Firstly, it further confirms that the bottleneck started sometime in the early Middle Ages – certainly before the 14th century and apparently before the 12th century, the time of the putative Jews found in Norwich.

Carmi and colleagues also compared the DNA of the Erfurt Jews to modern genomes from around the Levant and the Mediterranean to figure out their ancestry. The most statistically probable model indicates that both groups of Erfurt Ashkenazim could trace 65 percent of their ancestry to southern Italy, 19 percent to the Levant and 16 percent to Eastern Europe.

The strong Southern Italian component versus the Levantine one may seem surprising. But it should be noted that previous research has shown that in antiquity, particularly during the heyday of the Roman Empire, there was a large population influx into Italy from the Near East, which injected a strong Levantine genetic component into the Italian genetic mix.

Carmi emphasizes that these numerical estimates may not be precise because they rely on comparison with the genomes of modern people, which may be genetically different from those living in the same regions hundreds of years earlier.

Anyway, by comparing the DNA of the Erfurt Jews with that of modern Ashkenazim, Carmi’s team created a model of the group’s progression over the centuries. According to this model, the Ashkenazi population only began expanding 500-600 years ago, just after the time of the people buried in the Erfurt cemetery.

Before that, the large number of common ancestors that the DNA shows suggests that the bottleneck was a protracted event, which began more than 1,000 years ago and kept the Ashkenazi population small for centuries. Specifically, for nearly 20 generations, or around 500 years, the so called “effective population size,” that is the number of people who reproduced in every generation, may have been only 1,000 to 2,000, this model says.

Interestingly, this range is based on the modern Ashkenazi population, but when the researchers calculated the effective population size for the Erfurt sample, they came up with a number three times lower, 300 to 700.

This means that the ancestors of the Erfurt Jews experienced a much longer or more severe bottleneck, notes Prof. David Reich, a geneticist at Harvard University and one of the other authors of the paper. It also suggests that back in the Middle Ages, there were even more Ashkenazi groups out there that haven’t been identified yet and who must have had a shorter bottleneck. When they eventually mixed up with the rest of the Ashkenazim, they produced the average result we see in the modern population, Reich says.

“So what we are seeing is an archipelago of populations, who then start to coalesce into the homogenous Ashkenazi population that we know today,” he says.

While each isolated group may have experienced the bottleneck differently, it does look like the number of Ashkenazim stayed very low for a very long time.

“There is evidence that the bottleneck was ongoing for several generations, starting around the year 800-900,” Carmi says.

While not providing conclusive evidence, all of this is consistent with a scenario in which the founders of the Ashkenazim were living within a larger community, likely in Italy or somewhere else in Southern Europe, and then left to establish their own communities in Northern Europe.

“To remain culturally distinct they had to marry within the community, so the population remained small for a long time,” Carmi concludes.

How and why the initial migration north happened remains obscure, as does the subsequent split between the two distinct Ashkenazi groups identified at Erfurt.

Of course, Carmi cautions that his team’s study is based on the DNA extracted from people who lived in a specific period in a single medieval town. Future studies, particularly from older Ashkenazi burials across Europe, may reveal further twists and turns in this complex chapter of Jewish history, he says.

https://www.haaretz.com/archaeology/2022...ecc8940000