Y-DNA Haplogroup A 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: 22 December 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
SNP SYMBOLS:  Not on 2007 tree  Confirmed within subclade  Provisional  Private

A   M91, P97
�       A*   -
�       A1   P108
�      �       A1*   -
�      �       A1a   M31, P82    (formerly A1)
�      �       A1b   P114
�       A2   M6, M14, M23, M29/P3/PN3, M49, M71, M135, M141, M196, M206, M212, M276/P247, M277/P248, MEH1, P4, P5, P36.1
�      �       A2*   -
�      �       A2a   M114
�      �       A2b   P28
�      �       A2c   P262
�       A3   M32
�      �       A3*   -
�      �       A3a   M28, M59
�      �       A3b   M144, M190, M220, P289
�      �       �       A3b*   -
�      �       �       A3b1   M51, P100, P291
�      �       �      �       A3b1*   -
�      �       �      �       A3b1a   P71, P102
�      �       �       A3b2   M13, M127, M202, M219, M305
�      �       �      �       A3b2*   -
�      �       �      �       A3b2a   M171
�      �       �      �       A3b2b   M118


Y-DNA haplogroup A represents the oldest branching of the human Y chromosome tree, thought to have begun about 60,000 years ago. Like Y-DNA haplogroup B, the A lineage is seen only in Africa and is scattered widely, but thinly across the continent. These haplogroups have higher frequencies among hunter-gather groups in Ethiopia and Sudan, and are also seen among click language-speaking populations. Their patchy, widespread distribution may mean that these haplogroups are remnants of ancient lineages that once had a much wider range but have been largely displaced by more recent population events.

The most commonly seen sub-groups of haplogroup A are A2 (A-M6), A3b1 (A-M51), and A3b2 (A-M13). Sub-groups A2 and A3b1 are seen in South Africa, with A3b1 seen exclusively among the Khoisan. The range of A3b2 is restricted to Eastern Africa and at lower frequencies among Cameroonians. About 1.1% of African-Americans belong to the sub-group A3b2.


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.
Deng et al, Evolution and Migration History of the Chinese Population Inferred from the Chinese Y-chromosome Evidence. (pdf) Journal of Human Genetics, 49:339-348, 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.
Mohyuddin et al, Detection of Novel Y SNPs Provides Further Insights into Y Chromosomal Variation in Pakistan. Journal of Human Genetics, 2006.
Semino et al, Ethiopians and Khoisan Share the Deepest Clades of the Human Y-Chromosome Phylogeny. (pdf) American Journal of Human Genetics, 70:265-268, 2002.
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.
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.

Corrections/Additions made since 31 December 2007:

Contact Person for Haplogroup A: Ana Oquendo Pabon

Back to Main Page
Back to Y-DNA Tree Trunk
Back to SNP Index
Back to Papers Cited
Back to Glossary
Back to Listing Criteria

Copyright 2007, 2008, International Society of Genetic Genealogy. All Rights Reserved.