An article published in PLoS ONE, Y-chromosomal analysis of Greek Cypriots reveals a primarily common pre-Ottoman paternal ancestry with Turkish Cypriots, by Alexandros Heraclides and colleagues, insists on the potential origin of R1b and R1a lineages in Greece from Indo-European migrations, albeit with strong regional (and thus most likely temporal) differences. From the article’s discussion:
Although the exact origins and migratory patterns of R1a and R1b are still under rigorous investigation, it seems that they are linked to Bronze Age migrations from the Western Eurasian Steppe and Eastern Europe into Southern (including Greece) and Western Europe. Apparently, such migrations (especially as regards R1a) into Cyprus were limited.
Additionally, the Greek population has received considerable migrations during the Byzantine era and the Middle Ages from other Balkanic populations, such as Slavs[62,63], Aromanians (Vlachs), and Albanians (Arvanites)[65,66]. The former, is very likely to have increased R1a frequencies among Greeks. In fact, Fig 3 (also S7 Table) indicate that R1a increases gradually with increasing latitude in Greece. There is no historical evidence for such migrations into Cyprus during the same period.
The only Greek sub-population showing close genetic proximity to Cypriots (in terms of Y-haplogroup composition) is Cretan Greeks (Figs 3 and 4). It could be speculated that Cypriots and Cretans experienced very similar migratory events over the centuries, which were characterized by high influx from populations rich in haplogroups J2a and G2, and moderate in R1b, while very limited influx from populations rich in haplogroups R1a and I (Eastern and Northern/ Central Europe), as well as from populations rich in J1 (Middle East) and E-M81 (North Africa).
If R1b-M269 lineages are linked – as I have proposed – to Yamna migrations, and especially R1b-Z2103 to Palaeo-Balkan migrations, whereas R1a-M417 is to be linked to Corded Ware migrations, the reason for this latitude-dependent (and also longitude-dependent) presence of R1a-M417 subclades in Greece and is probably linked to the expansion of Slavic R1a-Z282 lineages to the north and west of Greece (and from there through intermarriages and migrations within Greece into other regions), and Iranian R1a-Z93 lineages to the east traditional Greek territory, into Asia Minor. The expansion of Balkan peoples (including Slavs, Albanian, and Aromanian peoples) might have brought with them R1b-M269*, I2, or R1a-Z282 subclades.
News of the article via Eurogenes.