Question about 1000 genome project

Question

[jonessara770]

Hi

I am reading 1000 genome papers and I am wondering why the greatest numbers of variant sites have been seen in African population? can you explain for me in a simple way to understand?

thanks

Answer 1

[abascalfederico]

Basically, modern humans evolved in Africa and lived there for long (don't know how long). Then, about 70-100 thousand years ago a sample of the people living in Africa went out to Eurasia, carrying with them a portion of the diversity existing at that time. That's why the highest diversity is preserved in Africa

[WouterDeCoster]

Yes, essentially all other populations went to some degree through a genetic bottleneck, limiting the genetic diversity when travelling farther away.

[Michael]

This is the hypothesis also sometime referred to as "Out of Africa" or better "Recent African origin of modern humans". The competing one is "Multiregional origin of modern humans". With respect to genetic variation, the former appears much more convincing to me.

Answer 2

[Michael]

The most common hypotheses should be explained here: https://en.wikipedia.org/wiki/Human_genetic_variation#History_and_geographic_distribution and see also the references.