Y-DNA Haplogroup I and its Subclades - 2008
The entire work is identified by the Version Number and date given on the Main Page. Directions for citing the document are given at the bottom of the Main Page.
Version History Last revision date for this specific page: 11 May 2008
Because of continuing research, the structure of the Y-DNA Haplogroup Tree changes and ISOGG does its best to keep the tree updated with the latest developments in the field. The viewer may observe other versions of the tree on the Web. Email Alice Fairhurst if the differences need clarification.

LINKS: Main Page Y-DNA Tree Trunk SNP Index Papers Cited Glossary Listing Criteria

CLADE/SUBCLADE SYMBOLS: Added Redefined

SNP SYMBOLS: Not on 2007 tree Confirmed within subclade Provisional Private

I   M170, M258, P19, P38, P212, U179   (P38 formerly I1)
•       I*    - (unobserved)
•      ; I1   M253, M307, M450/S109, P30, P40, S62, S63, S64, S65, S66, S107, S108, S110, S111    (formerly I1a)
•      •       I1*   -
•      •       I1a   M21    (formerly I1a2)
•      •       I1b   M227   (formerly I1a1)
•      •       •       I1b*   -
•      •       •       I1b1   M72    (formerly I1a1a)
•      •       I1c   P109
•      •       I1d   P259
•       I2   M438/P215/S31    (formerly I1b)
•      •       I2*   -
•      •       I2a   P37.2   (formerly I1b1)
•      •       •       I2a*   -
•      •       •       I2a1   M423    (not on Karafet 2008)
•      •       •      •       I2a1*   -
•      •       •      •       I2a1a   P41.2/M359.2   (formerly I1b1a)
•      •       •       I2a2   M26   (formerly I1b1b)
•      •       •      •       I2a2*   -
•      •       •      •       I2a2a   M161   (formerly I1b1b1)
•      •       I2b    M436/P214/S33, P216/S30, P217/S23, P218/S32   (formerly I1b2)
•      •       •       I2b*   -
•      •       •       I2b1   M223, P219/S24, P220/S119, P221/S120, P222/U250/S118, P223/S117    (formerly I1b2a - old I1c)
•      •       •      •       I2b1*   -
•      •       •      •       I2b1a   M284    (formerly I1b2a1)
•      •       •      •       I2b1b   M379    (formerly I1b2a2)
•      •       •      •       I2b1c   P78    (formerly I1b2a3)
•      •       •      •       I2b1d   P95    (formerly I1b2a4)

Notes

The tree has been revised to basically follow the structure of Karafet et al (2008) and also consults Underhill et al (2007b).
Identical SNPs that were discovered separately are listed in alphabetical order, not necessarily in the order of discovery, and separated by "/". Examples: M450/S109, M438/P215, P41.2/M359.2, M436/P214/S33, and P222/U250.
Thanks to Ken Nordtvedt, Natalie Myres, and Jim Wilson for their consultation on Haplogroup I.

Y-DNA haplogroup I is a European haplogroup, representing nearly one-fifth of the population. It is almost non-existent outside of Europe, suggesting that it arose in Europe. Estimates of the age of haplogroup I suggest that it arose prior to the last Glacial Maximum.

The two main subgroups of haplogroup I likely divided approximately 28,000 years ago:

I1-M253 et al has highest frequency in Scandinavia, Iceland, and northwest Europe. In Britain, haplogroup I1-M253 et al is often used as a marker for "invaders," Viking or Anglo-Saxon. The I1b-M227 subclade is concentrated in eastern Europe and the Balkans and appears to have arisen in the last one thousand to five thousand years. It has been reported in Germany, Czech Republic, Poland, Estonia, Ukraine, Switzerland, Slovenia, Bosnia, Macedonia, Croatia, and Lebanon.

I2-M438 et al includes I2* which shows some membership from Armenia, Georgia and Turkey; I2a-P37.2, which is the most common form in the Balkans and Sardinia; I2a2-M26 is especially prevalent in Sardinia. I2b-M436 et al reaches its highest frequency along the northwest coast of continental Europe. I2b1-M223 et al occurs in Britain and northwest continental Europe. I2b1a-M284 occurs almost exclusively in Britain, so it apparently originated there and has probably been present for thousands of years.

References:

Athey et al, Resolving the Placement of Haplogroup I-M223 in the Y-chromosome Phylogenetic Tree. (pdf) Journal of Genetic Genealogy, 1:54-55, 2005.
Cinnioglu et al, Excavating Y-chromosome Haplotype Strata in Anatolia. (pdf) Human Genetics. 114:127-148, 2004.
Karafet et al, New Binary Polymorphisms Reshape and Increase Resolution of the Human Y-Chromosomal Haplogroup Tree. Abstract. Genome Research, published online April 2, 2008. Supplementary Material.
Rootsi et al, Phylogeography of Y-Chromosome Haplogroup I Reveals Distinct Domains of Prehistoric Gene Flow In Europe. American Journal of Human Genetics, 75:128-137, 2004.
Scheinfeldt et al, Unexpected NRY Chromosome Variation in Northern Island Melanesia. (Link and comments from Dienekes' Anthropological Blog) Society for Molecular Biology, 2006.
Sims et al, Sub-Populations Within the Major European and African Derived Haplogroups R1b3 and E3a Are Differentiated by Previously Phylogenetically Undefined Y-SNPs. Human Mutation: Mutation in Brief #940, Online, 2007.
Underhill et al, New Phylogenetic Relationships for Y-chromosome Haplogroup I: Reappraising its Phylogeography and Prehistory. in Rethinking the Human Evolution, Mellars P, Boyle K, Bar-Yosef O, Stringer C, Eds. McDonald Institute for Archaeological Research, Cambridge, UK, pp. 33-42, 2007b.
Underhill et al, The Phylogeography of Y Chromosome Binary Haplotypes and the Origins of Modern Human Populations. (pdf) Annals of Human Genetics, 65:43-62, 2001.
Underhill et al, Y Chromosome Sequence Variation and the History of Human Populations. (pdf) Nature Genetics, 26: 358-361, 2000.
Y Chromosome Consortium (YCC), A Nomenclature System for the Tree of Human Y-Chromosomal Binary Haplogroups. Genome Research, 12:339-348, 2002.

Additional Resources:
Bob Waterouse, Haplogroup I Y-DNA Project
Charles Moore, Haplogroup I Subclade Cross-Reference (.xls file)
Ken Nordtvedt, Modal Haplotypes for Y-Haplogroup I Varieties
I1a Project Team (Rebekah Canada, Phil Goff, Aaron Hill, Ken Nordtvedt, Steve Transgrud, Samuel Theil), Y-DNA Haplogroup I Subclade I1a
Phil Goff, Deep Ancestry of I1a DYS19=16 Cluster
Ron Scott, I1a and I1b: Frequency Distribution of Extended Haplotypes Gathered from YSearch
Tim Weakley, I1b2* Project Database
Lewis Banks, Y-Haplogroup I1b2 Project
Grant & Jeffrey, I1c Y-Clan Study (now I1b2a)

Contact People for Haplogroup I: Phil Goff or Whit Athey

Corrections/Additions made since 31 December 2007:

Added Karafet et al (2008) and Underhill et al (2007b)on 4 May 2008.
SNPS added on 4 May 2008: M423, M436, M438, M450, P109, P212, P214, P215, P216, P217, P218, P219, P220, P221, P222, P223, P259, S107, S108, S109, S110, S111, U250.
M72 is no longer coded private on 5 May 2008.
Removed Capelli et al (2005), Karlsson et al (2006) and Sengupta et al (2007) as they did not identify new SNPs in Haplogroup I or significantly add to the knowledge of the structure of Haplogroup I on 6 May 2008.
Revised the relative placement on M21, M227, M423 and M26 and haplogroup description to be more in alignment with Karafet et al (2008) on 11 May 2008.
Added Charles Moore in Additional References and made M450/S109 as equivalent on 11 May 2008.

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