Description
Haplogroup A is the root of the entire human Y-chromosome phylogenetic tree. All men alive today descend from the patrilineal ancestor who defines this haplogroup. The deepest branches of A are found exclusively in Africa, predominantly among the Khoisan peoples of southern Africa and some Ethiopian and Sudanese groups, reflecting the African origin of modern humans.
Interesting Fact
The deepest-known human Y-chromosome, belonging to a man from South Carolina with Mbo ancestry, pushed the divergence of haplogroup A00 to approximately 340,000 years ago — well before the emergence of anatomically modern Homo sapiens.
Distribution by Ethnicity
| Ethnic distribution | Region | Frequency | Sample |
|---|---|---|---|
| Khoisan (San) | Southern Africa | n=80 | |
| Hadza | East Africa | n=50 | |
| Mbo (Cameroon) | Central Africa | n=40 |
Tags
References
- Mendez et al. (2013) — An African American paternal lineage adds an extremely ancient root to the human Y chromosome phylogenetic tree. American Journal of Human Genetics 92(3), 454–459.
- Cruciani et al. (2011) — A revised root for the human Y chromosomal phylogenetic tree: the origin of patrilineal diversity in Africa. American Journal of Human Genetics 88(6), 814–818.