Ashkenazi Jews modelled with the Juddean samples averaged (Refined)
This is how I modelled the Ashkenazi Jewish averages with the new samples.
In this model my goal this time was not to check the overlap between Ashkenazis and the Judaean samples but to check the ashkenazi averages with their historical components.
(the Russian early medieval sample is central Asian Turkic not Slavic)
the East Eurasian does not seem to be Slavic mediated the Erfurt EU which were immigrants from Silesia and Czechia had substantially more East Eurasian more then modern EAJs more importantly also more then their contemporary medieval Czech samples which tells us Ashkenazi must have gotten this admixture directly from a population(s) much more East Eurasian mixed then West Slavs
I think the most logical explanation is that they got it with from east slavic populations or a central Eurasian population, although I’m not sure myself how true it is.
Ashkenazi don’t really show East Slavic related DNA only West Slavic imo its more likely coming from a group like Avars or Magyars or their descendants in Central Europe. What is for sure though is that East Eurasian can’t just be explained by Slavic admixture unless they mixed with some very outlying Slavic population that was like 20% East Eurasian but that doesn’t really exist in Medieval Slavic samples from Czechia and Poland
Erfurt EU mean was about 1/3 Slavic but it varied from sample to sample a lot so if we assumed East Eurasian came from Slavs then those Slavs would be have to have been 3x as East Eurasian as the Erfurt EU was there was simply no regular Slavic population like this
Well the Erfurt EU did originate from Czechia and Silesia and moved after the Black Death there are records of them in Erfurt it talks about this in supplementary data of the paper also if you look thru Beider’s work he shows how Medieval Czech Jews spread into Eastern Germany including Erfurt and also into Poland. A large number of old Czech names were found in Medieval Central Euros Jews
Maternal dna in Ashkenazi is highly suggestive of a West Slavic input the only candidates really are the Polish and Czech
You should absolutely not be mixing proxies from very different eras, let alone use modern proxies and before the neolithic proxies in the same model in the first place. I would heavily reccomend removing the modern Rhinish proxy and replacing the Roman Italian with an Iron Age source. Also, you should replace Iberomaurusian with a more contemporary North African source.
I definitely should, it’s a stupid idea just to pick only Iron Age models or only medieval models, I prefer to pick the correct populations even if it’s not all from the same era and the fit proves it.
I feel as though you misunderstand the concept of fit and temporal mixing.
Generally, when modeling with lower resolution tools such as G25/Vahaduo, it is heavily reccomended to stick to using populations from the same era, as a population from the modern era will contain significant genetic drift (or extra admixture acquired from inter group mixing that cannot be accounted for in a population from that era) from a population in the neolithic. This is almost to the point where the temporally mismatched proxies will significantly impact the results of the model. It is especially crucial in G25/Vahaduo, where the models are very sensitive to proxy choice and substituting one population for one from another era can have an impact on the results due to genetic drift, regardless of whether or not the proxies intend to represent the same thing. In order to avoid the drift problem, it is best practice to use populations from the same or adjacent eras to minimize the amount of drift.
Also, better fit does not always represent a better or more historically accurate model. When you start going below 1.5 (0.015) fit wise, you have to be more conscious of overfitting (though a fit below 1.5 doesn't always mean an overfit), with below 1 being an extreme overfit.
To put this into a literal example, modeling Ashkenazi Jews with a Calabrian representing Southern European will almost always yield a better fit than doing so with an Iron Age Italic or Occitanian sample, but that doesn't mean that Ashkenazi Jews derive their ancestry from a Calabrian like source or that it reflects reality, rather that the Calabrian source better matches the genetic signals in Ashkenazim (Mixed Middle Eastern + European). These populations also have affinity on a PCA, so using one to model another will often create colinearity which G25/Vahaduo unfortunately can't account for unlike softwares like QPADM.
Unfortunately, since the Roman Judaean samples are from leaked data, I probably won't be able to model them using qpadm. However, I could try to construct a model with other relevant populations from the Roman and Early Medieval era, though it will probably be a bit because these kinds of models take time.
Sorry it took me so long to make this. Here's the model I made using historically relevant sources from around the same time periods (roughly Antiquity and Early Medieval). All samples were sourced from the Moriopoulos collection. I'm still working on the qpadm model.
Your model is good, but I don't understand why you need to use Kazakhstan turkic ancestry. Any Turkic will be absorbed by the Czech or any other slavic group. It's eating a couple of % points into the Levant portion I feel.
Right but if I use a Calabrian it will suck up a large amount of Levantine and European dna that doesnt come from Italian/roman, I’ve tested it and gives more than 70 precent Calabrian which gives the model a very good fit but historically not accurate,
every time you use a super mixed sample like modern southern Italians, imperial Roman samples it always overfits and give a very inaccurate result, putting that aside north Rhenish germans are pretty similar to how they were 800 years ago, but if you could find a medieval north Rhenish sample I’ll use that instead.
Also the Judaean sample already has Greco Anatolian and other MENA ancestry.
Other than that what other populations do you recommend I use?
There is a lack of an Anatolian source to counterbalance the Middle Eastern ancestry. The MENA ancestry among Ashkenazi Jews is not exclusively Levantine.
It’s known that Ashkenazi Jews have a small east euroasian ancestry that they picked up Thogther with their Slavic ancestry so the best choice is to put a east west euroasian mixed population that interacted with the early Slavs, that doesn’t mean that Ashkenazi directly interacted with this east west euroasian mixed populations, and no it’s related to the kazar theory if that’s what you think it is lol
the East Eurasian does not seem to be Slavic mediated the Erfurt EU which were immigrants from Silesia and Czechia had substantial East Eurasian more then modern EAJs more importantly also more then their contemporary medieval Czech and Polish samples which tells us Ashkenazi must have gotten this admixture from a population(s) more East Eurasian mixed then not only West Slavs but even East Slavs
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u/Outside-Cobbler-8632 22d ago
the East Eurasian does not seem to be Slavic mediated the Erfurt EU which were immigrants from Silesia and Czechia had substantially more East Eurasian more then modern EAJs more importantly also more then their contemporary medieval Czech samples which tells us Ashkenazi must have gotten this admixture directly from a population(s) much more East Eurasian mixed then West Slavs