The episode of genetic drift defining the migration of humans out of Africa is derived from a large east African population size

PLoS One. 2014 May 20;9(5):e97674. doi: 10.1371/journal.pone.0097674. eCollection 2014.


Human genetic variation particularly in Africa is still poorly understood. This is despite a consensus on the large African effective population size compared to populations from other continents. Based on sequencing of the mitochondrial Cytochrome C Oxidase subunit II (MT-CO2), and genome wide microsatellite data we observe evidence suggesting the effective size (Ne) of humans to be larger than the current estimates, with a foci of increased genetic diversity in east Africa, and a population size of east Africans being at least 2-6 fold larger than other populations. Both phylogenetic and network analysis indicate that east Africans possess more ancestral lineages in comparison to various continental populations placing them at the root of the human evolutionary tree. Our results also affirm east Africa as the likely spot from which migration towards Asia has taken place. The study reflects the spectacular level of sequence variation within east Africans in comparison to the global sample, and appeals for further studies that may contribute towards filling the existing gaps in the database. The implication of these data to current genomic research, as well as the need to carry out defined studies of human genetic variation that includes more African populations; particularly east Africans is paramount.

Publication types

  • Clinical Trial
  • Multicenter Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Africa, Eastern
  • Black People / genetics*
  • Electron Transport Complex IV / genetics*
  • Evolution, Molecular*
  • Female
  • Genetic Drift*
  • Human Migration*
  • Humans
  • Male
  • Phylogeny*


  • Electron Transport Complex IV

Grants and funding

The study is partially funded by EVIMalaR FP7 EC research fund, the MalariaGen consortium and the African Development Fund (ADF) through the National Board for Higher Education – Eritrea. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.