First, we need more samples from late antiquity Balkans, including Greek Macedonia, Epirus, Moesians and Illyrians. This will give us a good idea of the preinvasion genetic landscape. As I mentioned in another post, we would be able to distinguish between the ancestry of slavic admixed individuals in Greece. This is due to the fact that the palaeoBalkan component of the admixed Slavs is not the same with that of preinvasion Greeks, but more similar to North-western Balkans. You can read about this here:
https://anthrogenica.com/showthread....kans-and-Italy
You can see this in the attached image. The "Serbian" component is nearly absent from Greek islanders, but peaks in areas affected by the Slavic migrations. David told me that this is a reasonable model, although he has his reservations about the Imperial Roman sample being representative of preinvasion Greeks.
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