Summary
In human genetics, Haplogroup R-DF27 (R1b1a2a1a2a) is a Y-chromosome haplogroup which is a subdivision of haplogroup R-M269 (more specifically, its subclade R-) defined by the presence of the marker DF27 (also known as S250). Along with R-U152 and R-L21, the lineage is to a significant extent associated with Proto-Celtic, Celtic and later Celtiberian movements.
| Haplogroup R-DF27 | |
|---|---|
 | |
| Possible time of origin | 4,200 years BP |
| Possible place of origin | Central Europe |
| Ancestor | R-M269, R-L151, P312, Z40481, ZZ11 |
| Defining mutations | R-M167, R-M153 |
| Highest frequencies | Gallo-Iberians[citation needed] (Basques, Catalans, Galicians, Asturians, Gascons, Béarnese and others) |
It arose comparatively recently, after the beginning of the European Bronze Age, and is mostly prevalent in the population of the Pyrenees region. The regions where it has been mostly found are Basque Country, Navarre, Asturias, Galicia, Portugal, Aragon, Catalonia, Pyrénées-Atlantiques as well as some presence in Great Britain and Ireland, though it has been found in smaller quantities as far away as Germany and Poland.
Specific subclades of DF27 have been associated with specific groups of people, for example R-M167 is associated with the Catalans and R-M153 is associated with the Basques.[1]
Genetic testing edit
The technology to test for DF27 was developed by Thomas Krahn, then of Family Tree DNA. This marker was discovered to exist among people who had taken part in the Human Genome Diversity Project. Richard A. Rocca made a pioneering study of DF27, which was published in 2012 in the article Discovery of Western European R1b1a2 Y Chromosome Variants in 1000 Genomes Project Data, in the peer-reviewed journal PLOS Biology. He based his study on 208 people who had tested as R-M269 and were from Great Britain, Tuscany (Italy), Spain, Finland, Utah (United States) and Latin American (Colombia, Puerto Rico, etc).[2]
Distribution edit
According to a 2017 article published in Springer Nature entitled, Analysis of the R1b-DF27 haplogroup shows that a large fraction of Iberian Y-chromosome lineages originated recently in situ, DF27 was found in frequences of 40% in the general population of the Iberian Peninsula and in particular spikes at 70% among the Basques. Overall in France it accounts for between 6–20% of the population but has a high level in the Pyrenees area. It is estimated to have developed around 4,200 years ago in north-eastern Prehistoric Iberia as the Neolithic made way for the Atlantic Bronze Age. The DF27 subgroups correspond closely to the various pre-Roman kingdoms formed by the Celtiberians.[3]
Subclades edit
Y-DNA R-DF27 subclades edit
- DF27*
- R1b1a1a2a1a2a1-Z195
- ZZ12_1
- SK1907
Y-DNA backbone tree edit
See also edit
References edit
- ^ "Evidence of Pre-Roman Tribal Genetic Structure in Basques from Uniparentally Inherited Markers". Oxford Journals. 26 January 2018.[dead link]
- ^ Rocca, Richard A.; Magoon, Gregory; Reynolds, David F.; Krahn, Thomas; Tilroe, Vincent O.; Op Den Velde Boots, Peter M.; Grierson, Andrew J. (26 January 2018). "Discovery of Western European R1b1a2 Y Chromosome Variants in 1000 Genomes Project Data: An Online Community Approach". PLOS ONE. 7 (7). PLOS Biology: e41634. doi:10.1371/journal.pone.0041634. PMC 3404022. PMID 22911832.
- ^ "Analysis of the R1b-DF27 haplogroup shows that a large fraction of Iberian Y-chromosome lineages originated recently in situ". Springer Nature. 26 January 2018.
Further reading edit
- Dissection of the DF27 paternal lineage at Forensic Science International
- Characterization of the Iberian Y chromosome haplogroup R-DF27 in Northern Spain at Forensic Science International
Bibliography edit
- Manco, Jean (2015). Ancestral Journeys: The Peopling of Europe from the First Venturers to the Vikings. Thames and Hudson. ISBN 978-0500292075.
External links edit
- R-DF27/S250 at The Big Tree
- R DF27 and Subclades at Family Tree DNA
- R1b-DF27.com