Y-DNA Haplogroup R, SNPs, and Subclades (e.g. R1a, R1b > R1b-M222) |
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Haplogroups are large branches of the ancient human family tree, as evidenced by specific SNP |
mutations. Haplogroups have letter names A-R assigned by the Y Chromosome Consortium [39]. |
Sub-divided haplogroups (subclades) can have long string names (e.g. R1b1a1a2a1a2c1a1a1a1), |
was shown on the isogg tree [17], although our current practice shows only the ‘terminal SNP’: |
e.g. FTDNA’s M269, R-M269, or R1b-M269, all showing M269 as one man’s terminal SNP; |
alternatively, M222, R-M222, or R1b-M222, all show M222 (below M269) as the terminal SNP; |
or FGC19846, R-FGC19846, or R1b-FGC19846, a lower-level FGC19846 terminal SNP [40]. |
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Y-DNA haplogroup R-M207 is believed to have arisen approximately 27,000 years ago in Asia. |
The two currently defined first-level subclades are R1 and R2. R1-M173 is estimated to have |
arisen during the height of the Last Glacial Maximum (LGM), about 18,500 years ago, most |
likely in southwestern Asia. The two most common descendant clades of R1 are R1a and R1b. |
R1a-M420 is believed to have arisen on the Eurasian Steppe or the Indus Valley, and today is |
most frequently observed in eastern Europe and in western and central Asia [17]. |
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R1b-M343 is believed to have arisen in southwest Asia and today its subclades (e.g. R1b-M269, |
> R1b-P312, and > R1b-M222) are found in various distributions across Eurasia and Africa. |
R1b1a2-M269 is estimated to have arisen approximately 4,000 to 8,000 years ago in southwest |
Asia and to have spread into Europe from there. The Atlantic Modal Haplotype, or AMH, is the |
most common STR haplotype in R1b1a2a1a-L11/PF6539/S127 and most European R1b1a2 is |
part of R1b1a2a1a1-M405/S21/U106 or R1b1a2a1a2-P312/PF6547/S116 (> R1b-M222) [17]. |
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Haplogroup R1b-M222 subclade within R1b-L21 is defined by the presence of the M222 SNP. |
It is particularly associated with male lines which are Irish or Scottish, especially northern Irish. |
This specific subclade has been linked to the Uí Néill dynastic kindred of ancient Ireland, with |
the closely related Connachta dynasties, the Uí Briúin and Uí Fiachrach, and with Scotland [41]. |
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SNPs (single nucleotide polymorphisms) confirm the Y haplogroup by determining if a SNP |
has mutated from its derived or ancestral state. SNPs are usually found on different areas of the |
Y-chromosome than where the Y-STR markers are located [14]. When a scientist discovers a |
new SNP, they can name the new SNP with their specific prefix and their sequential number [42] |
(so, L21 is the 21st ‘L’ SNP, M222 is Peter Underhill / Stanford’s 222th ‘M’, and FGC19851 > |
FGC19846 > FGC19844 are 3 recent SNPs discovered by FGC (Full Genomes Corporation)). |
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Information about most known SNPs can be found on the isogg tree [17], on the big tree [43], |
at SNPedia [44], at YSEQ [45], and at isogg’s YBroswe [46] (confusing, with too much detail). |
And studies of the mutation rates for Y-DNA SNPs are at the leading edge of current genetic |
science, with various estimates of 137, 144, 150, and 160 years per mutation [47] [48] [49] [50]. |
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McAninch Y-DNA Status Report 2016: 6 of 8: Haplogroup R, SNPs, Sub-clades, R1b-M222 |
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McAninch Family History NL v.XXIV n.1 / April 2016 / Copyright Frank McAninch / pg.2016-07 |
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