Genetic history from the Middle Neolithic to present on the Mediterranean island of SardiniaPublished: 24 February 2020
https://www.nature.com/articles/s41467-020-14523-6Обновлённые данные:
The 1240k read capture data allowed us to call several R1b subclades in ancient individuals (see Supp. Fig. 7 for overview of available markers). While R1b-M269 was absent from our sample of ancient Sardinians until the Nuragic period, we detected R1b-V88 equivalent markers in 11 out of 30 ancient Sardinian males from the Middle Neolithic to the Nuragic with Y haplogroup calls. Two ancient individuals carried derived markers of the clade R, but we could not identify more refined subclades due to their very low coverage (Supp. Data 1B). The ancient geographic distribution of R1b-V88 haplogroups is particularly concentrated in the Seulo caves sites and the South of the island (Supp. Data 1B).
At present, R1b-V88 is prevalent in central Africans, at low frequency in present-day Sardinians, and extremely rare in the rest of Europe58. By inspecting our reference panel of western Eurasian ancient individuals, we identified R1b-V88 markers in 10 mainland European ancient samples (Fig. 8 ), all dating to before the Steppe expansion (ą 3k years BCE). Two very basal R1b-V88 (with several markers still in the ancestral state) appear in Serbian HGs as old as 9,000 BCE (Fig. 9), which supports a Mesolithic origin of the R1bV88 clade in or near this broad region. The haplotype appears to have become associated with the Mediterranean Neolithic expansion - as it is absent in early and middle Neolithic central Europe, but found in an individual buried at the Els Trocs site in the Pyrenees (modern Aragon, Spain), dated 5,178-5,066 BCE59 and in eleven ancient Sardinians of our sample. Interestingly, markers of the R1b-V88 subclade R1b-V2197, which is at presentday found in Sardinians and most African R1b-V88 carriers, are derived only in the Els Trocs individual and two ancient Sardinian individuals (MA89, 3,370-3,110 BCE, MA110 1,220-1,050 BCE) (Fig. 9). MA110 additionally carries derived markers of the R1b-V2197 subclade R1b-V35, which is at present-day almost exclusively found in Sardinians.
This configuration suggests that the V88 branch first appeared in eastern Europe, mixed into Early European farmer individuals (after putatively sex-biased admixture), and then spread with EEF to the western Mediterranean. Individuals carrying an apparently basal V88 haplotype in Mesolithic Balkans and across Neolithic Europe provide evidence against a previously suggested central-west African origin of V8861. A west Eurasian R1b-V88 origin is further supported by a recent phylogenetic analysis that puts modern Sardinian carrier haplotypes basal to the African R1b-V88 haplotypes. The putative coalescence times between the Sardinian and African branches inferred there fall into the Neolithic Subpluvial (“green Sahara”, about 7,000 to 3,000 years BCE).
Previous observations of autosomal traces of Holocene admixture with Eurasians for several Chadic populations provide further support for a speculative hypothesis that at least some amounts of EEF ancestry crossed the Sahara southwards. Genetic analysis of Neolithic human remains in the Sahara from the Neolithic Subpluvial would provide key insights into the timing and specific route of R1b-V88 into Africa - and whether this haplogroup was associated with a maritime wave of Cardial Neolithic along Western Mediterranean coasts and subsequent movement across the Sahara.
Overall, our analysis provides evidence that R1b-V88 traces back to eastern European Mesolithic hunter gatherers and later spread with the Neolithic expansion into Iberia and Sardinia. These results emphasize that the geographic history of a Y-chromosome haplotype can be complex, and modern day spatial distributions need not reflect the initial spread.
Тема: Центрально-Африканские R1b-V88 (Прочитано 29275 раз)