The origin of Fennoscandinavian and Baltic N in Kola Peninsula?

I made several attempts to find downstream mutations of ancient Kola Peninsula samples BOO002 and BOO004.  Only those two belong to male remains and are tested L392, in my tests L392 is also the terminal mutation.  Both belong to the same terminal mutation and have no downstream mutations.  Yfull gives age estimates for L392:  formed 6400 ybp, TMRCA 4800 ybp.  Those two male samples were published by Lamnidis et al. 2018 and the age estimate was 3473 ± 87 calBP.  So there have to be 4800-around 3500=1300 years difference between estimates of the whole clade (by TMRCA) and Kola Peninsula sample ages, indicating migrations and/or  founder effects. Considering this we can say that Kola samples are not so far from the TMRCA estimate of all L392 samples, including all downstreams. But because Kola samples have not downstream mutations, we have to consider them as belonging to the forefather clade of all living people carrying mutation L392.  I made a migration model based on this assumption.   


N-L1026/L392 formed 6400 ybp, TMRCA 4800 ybp
-  N-VL29 formed 4100 ybp, TMRCA 3600 ybp
--   N-BY33087 formed 1750 ybp, TMRCA 950 ybp 
        id:YF11696FIN [FI-ES]
---     N-BY33088 formed 950 ybp, TMRCA 950 ybp 
           id:YF14404RUS [RU-NGR]
           id:YF11830FIN [FI-IS]

We see that VL29, which is one of main European branches of N, is only 1200 years younger than the upstream branch in Kola Peninsula.   You can click the branch name to see more details on Yfull pages.  We also see that there has obviously been a founder effect in Russia and Finland.  Nevertheless, 1200-1300 years is the same time gap than we saw between the estimate of the L392 and pure L392's in Kola Peninsula.  It is only a short leap from  L392 to VL29, where ever it happened, but why not from the arctic zone to the boreal forest. 

Another downstrean branch of L392:


N-Z1936 formed 4800 ybp, TMRCA 4300 ybp

This obviously can be considered as a straightforward downstream of L392, particularly because Z1936 mostly exists in the neighborhood of Kola Peninsula. 

--   N-Z1934 formed 4300 ybp, TMRCA 4300 ybp
         id:YF15740RUS [RU-MOW]

---    N-Z1928 formed 4300 ybp, TMRCA 3300 ybp


----    N-Z1925 formed 3300 ybp, TMRCA 3000 ybp

-----      N-Y29767 formed 3000 ybp, TMRCA 600 ybp
             id:YF08170SWE [SE-BD]
             id:YF04765SWE [SE-BD]
-----      N-Y62904 formed 3000 ybp, TMRCA 1200 ybp
             id:YF12523FIN [FI-LS] 
             id:YF06892FIN [FI-OL]

The more we go down the branch Z1936, the more it becomes purely Finnish and shows clade ages below 2000 years, meaning an obvious local founder effect.

It is also possible that another pure L392 lived southward and was the origin of the East European migration, but we have no evidence so far.   Considering the question of how the Siberian admixture of the L392 branch disappeared in some North European regions, we have several explanations.  The first explanation is due to getting more mixed.  This is supported by the fact that even recently the Siberian admixture becomes stronger in the north and disappears in the south.  Another explanation is that the original L392 was not Siberian at all, but then we have to search evidences how the Siberian admixture reached Fennoscandinavia and even the westernmost Scandinavia in the north, if not by arctic migrations via Kola Peninsula (including L392 and other northeast migrants).  So if we are not happy with one L392 and one Siberian and we still try to find alternatives we could have two distinct L392 migrations, one via Kola and another from east to the Baltic Sea, then we could have three distinct migrations of L392, one to Kola, second to Estonia to explain Baltic Finns and third to explain Balts.  Sound like a slippery slope. 

If the Kola postulate is right, then we obviously had two southward migrations:  one from Kola to Scandinavia and Western Finland through the Baltic Sea, ending up to the shores of Baltic region, another from Kola to White Sea Region, Karelia and Eastern Finland.  


You can browse the data by clicking the branch id's above or going to the Yfull straight here.