Where did the Proto-Celts originally come from? Where does y-DNA R1b originate? And what were their blood type frequencies before arriving in Western Europe?
What do Celts have in common and who are their ancestors?
Not too long ago, I have published The original Basques were not Celtic. Today, Basque DNA is very different, especially within the male lineages, from the original Proto-Basques. The original Basque y-DNA was mainly I2a (some G2a which is still dominant in the Caucasus regions), but Celtiberian R1b men slaughtered the original I2a Basque speaking men, procreated with their women, and only left a few I2a (original) Basque men in the population.
The question remains who is responsible for the rh negative blood factor within us. So let’s look what frequencies may have looked like during the Bronze age:
If we compute expected phenotypic frequencies, this suggests that around around 65% of Mesolithic hunter-gatherers would have been type O, compared to around 40% in present-day Europeans, and around 40% of Steppe-ancestry individuals would have been Rh-, compared to around 24% of hunter-gatherers, 4% of early farmers, and about 16% of present-day Europeans.
Steppe (ST): Bronze Age individuals with “Yamnaya-like” ancestry
Although red hair is an almost exclusively northern and central European phenomenon, isolated cases have also been found in the Middle East, Central Asia (notably among the Tajiks), as well as in some of the Tarim mummies from Xinjiang, in north-western China. The Udmurts, an Uralic tribe living in the northern Volga basin of Russia, between Kazan and Perm, are the only non-Western Europeans to have a high incidence of red hair (over 10%). So what do all these people have in common? Surely the Udmurts and Tajiks aren’t Celts, nor Germans. Yet, as we will see, all these people share a common ancestry that can be traced back to a single Y-chromosomal haplogroup: R1b.
The Scots and Irish also happen to have the highest percentage of combined Celto-Germanic R1a (L664 and Z283 subclades) and R1b (P312 and U106), and therefore the highest percentage of patrilineal Yamna ancestry.
Yamnayan DNA tested by Haak (2015), Wilde (2014), Mathieson (2015) showed that Yamna people (or at least the few elite samples concerned) had predominantly brown eyes, dark hair, and had a skin colour that was moderately light, lighter than Mesolithic Europeans, but somewhat darker than that of the modern North Europeans. This is not unexpected considering that these samples had about 25% of recent admixture from the Iranian Plateau (before the Indo-European migrations brought Northeast European genes to the region), which would have darkened their pigmentation. Other tests have confirmed that the vast majority of Mesolithic Europeans had blue eyes, and the high incidence of red hair among Northwest Europeans (who have the highest percentage of Yamna ancestry) as well as in the Volga-Ural region and in ancient Chinese depictions of the Tocharians from the Tarim Basin strongly suggest that red hair was found among Yamnayans, and that the genes for red hair (which also include some mutations for fair hair) were spread by R1b Indo-Europeans. (=> see The Origins of Red Hair)
Some of you have brought up Scythia, but let’s remember the timeline of the migrations.
Historical spread of Iranian peoples/languages: Scythia, Sarmatia, Bactria and the Parthian Empire in about 170 BC (evidently before the Yuezhi invaded Bactria). Modern political boundaries are shown to facilitate orientation.
The high CHG admixture in elite Kurgan samples was not found in earlier Steppe cultures, apart from a single R1b sample from the Khvalynsk culture that differed from non-R1b samples in that regard. This indicates that a foreign intrusion from the South Caucasus is responsible for this unusually elevated CHG among the Yamna elite. The considerably lower CHG admixture observed in German Bell Beaker and Unetice samples (average 10%), whih represent the advance of R1b tribes into Central Europe, hints that the rest of the Yamna population had higher Mesolithic European and lower Caucasian ancestry than the Yamna samples tested to date, and could consequently have looked more like modern Scottish and Irish people. This would mean mixed blue and brown eyes, and mixed hair colours with brown hair being predominant, but with a sizeable minority of red hair and perhaps also blond hair. Blond hair appears to have originated among Mesolithic Northeast Europeans, and is therefore be more common in populations with high levels of (Baltic, Slavic and Germanic) R1a.
