Y-DNA Haplogroup I and its Subclades
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Version History     Last revision date for this specific page: 17 December 2006

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
SNP SYMBOLS:  Not on 2005 tree  Confirmed within subclade  Provisional  Private

I   M170, M258, P19, U179
�       I*   -
�       I1   P38
�      �       I1*   -
�      �       I1a   M253, M307, P30, P40
�      �       �       I1a*   -
�      �       �       I1a1   M227   (formerly I1a4)
�      �       �       I1a2   M21
�      �       �       I1a3   M72
�      �       I1b   S31
�      �       �       I1b*   -
�      �       �       I1b1   P37.2 (formerly I1b)
�      �       �      �       I1b1*   -
�      �       �      �       I1b1a   P41.2 (M359.2) (formerly I1b1)
�      �       �      �       I1b1b   M26 (formerly I1b2)
�      �       �      �       �       I1b1b*   -
�      �       �      �       �       I1b1b1   M161 (formerly I1b2a)
�      �       �       I1b2    S23, S30, S32, S33 (added)    
�      �       �      �       I1b2*   -
�      �       �      �       I1b2a   M223, S24 (formerly I1c, also shown as I2)
�      �       �      �       �       I1b2a*   -
�      �       �      �       �       I1b2a1   M284 (formerly I1c1, also shown as I2a)
�      �       �      �       �       I1b2a2   M379
�      �       �      �       �       I1b2a3   P78
�      �       �      �       �       I1b2a4   P95


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. Probably, it was confined to the refuge in the Balkans during the last Ice Age, and then spread northward during the recolonization of northern Europe following the retreat of the glaciers.

There are two main subgroups of haplogroup I:


Alonso et al, The Place of the Basques in the European Y-chromosome Diversity Landscape. (available by subscription) European Journal of Human Genetics, 13:1293-1302, 2005.
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.
Behar et al, Contrasting Patterns of Y Chromosome Variation in Ashkenazi Jewish and Host Non-Jewish European Populations. (pdf) Hum Genet 114:354-365, 2004.
Capelli et al, Population Structure in the Mediterranean Basin: A Y Chromosome Perspective. (pdf) Annals of Human Genetics, 2005.
Cinnioglu et al, Excavating Y-chromosome Haplotype Strata in Anatolia. (pdf) Human Genetics. 114:127-148, 2004.
Cruciani et al, A Back Migration from Asia to Sub-Saharan Africa Is Supported by High-Resolution Analysis of Human Y-Chromosome Haplotypes. (pdf) American Journal of Human Genetics, 70:1197-1214, 2002.
Flores et al, Reduced Genetic Structure of the Iberian Peninsula Revealed by Y-chromosome Analysis: Implications for Population Demography. (available by subscription) European Journal of Human Genetics, 12:855-863, 2004.
Karlsson et al, Y-chromosome Diversity in Sweden - A Long-time Perspective. European Journal of Human Genetics, 1-8, 2006. (Comments on paper from Dienekes' Anthropological Blog - fee for paper from www.nature.com/ejhg)
Kivisild et al, The Genetic Heritage of the Earliest Settlers Persists in Both Indian Tribal and Caste Populations. (pdf) American Journal of Human Genetics, 72:313-332, 2003.
Nasidze et al, MtDNA and Y-chromosome Variation in Kurdish Groups. (abstract) Annals of Human Genetics, 69:401-412, 2005.
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.
Sengupta et al, Polarity and Temporality of High Resolution Y-chromosome Distributions in India Identify Both Indigenous and Exogenous Expansions and Reveal Minor Genetic Influence of Central Asian Pastoralists. (pdf) American Journal of Human Genetics, 78:202-221, 2006.
Shen et al, Reconstruction of Patrilineages and Matrilineages of Samaritans and other Israeli Populations from Y-Chromosome and Mitochondrial DNA Sequence Variation. (pdf) Human Mutation, 24:248-260, 2004.
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.
Valone et al, Y SNP Typing of African-American and Caucasian Samples Using Allele-Specific Hybridization and Primer Extension. (pdf) Journal of Forensic Science, 49:4, July 2004.

Additional Resources:
Lewis Banks, Y-Haplogroup I1b2 Project
Phil Goff, Deep Ancestry of I1a DYS19=16 Cluster
Grant & Jeffrey, I1c Y-Clan Study (now I1b2a)
Aaron Hill, Y-DNA Haplogroup I Subclade I1a
Andrew Lancaster, I Haplogroup called Ix
Andrew Lancaster, Report about Haplogroup I1* Clusters
Ken Nordtvedt, Modal Haplotypes for Y-Haplogroup I Varieties

Contact People for Haplogroup I: Phil Goff or Whit Athey

Corrections/Additions made since 10 April 2006:

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