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warwick
12-10-2014, 02:42 AM
The team has sequenced the genome of five living individuals from a hunter/gatherer tribe in Southern Africa, and compared them with 420,000 genetic variants across 1,462 genomes from 48 ethnic groups of the global population.

Through advanced computation analysis, the team found that these Southern African Khoisan tribespeople are genetically distinct not only from Europeans and Asians, but also from all other Africans.

The team also found that there are individuals of the Khoisan population whose ancestors did not interbreed with any of the other ethnic groups for the last 150,000 years and that Khoisan was the majority group of living humans for most of that time until about 20,000 years ago.

Their findings mean it is now possible to use genetic sequencing to reveal the ancestral lineage of any ethnic group even up to 200,000 years ago, if non-admixed individuals are found, like in the case of the Khoisan. This will show when in history there have been important genetic changes to an ancestral lineage due to intermarriages or geographical migrations that may have occurred over the centuries.

http://www.sciencedaily.com/releases/2014/12/141204074144.htm

Gary Corbett
12-14-2014, 03:48 AM
I actually know a girl on 23andMe who's mother is one of those people.
Her father came from Dutch soldiers and other Europeans.
She has a segment in common with one of my cousins-way too ancient to trace.
She is 'different-looking'.She is also beautiful and sweet.

dp
01-28-2015, 07:15 PM
One of humankind’s most ancient lineages ...http://www.sciencedaily.com/releases/2014/12/141204074144.htm

Interesting stuff. Here's something related:

Ancient west Eurasian ancestry in southern and eastern Africa,
Joseph K. Pickrell, PNAS,
DOI: 10.1073/pnas.1313787111

Abstract
The history of southern Africa involved interactions between indigenous hunter–gatherers and a range of populations that moved into the region. Here we use genome-wide genetic data to show that there are at least two admixture events in the history of Khoisan populations (southern African hunter–gatherers and pastoralists who speak non-Bantu languages with click consonants). One involved populations related to Niger–Congo-speaking African populations, and the other introduced ancestry most closely related to west Eurasian (European or Middle Eastern) populations. We date this latter admixture event to ∼900–1,800 y ago and show that it had the largest demographic impact in Khoisan populations that speak Khoe–Kwadi languages. A similar signal of west Eurasian ancestry is present throughout eastern Africa. In particular, we also find evidence for two admixture events in the history of Kenyan, Tanzanian, and Ethiopian populations, the earlier of which involved populations related to west Eurasians and which we date to ∼2,700–3,300 y ago. We reconstruct the allele frequencies of the putative west Eurasian population in eastern Africa and show that this population is a good proxy for the west Eurasian ancestry in southern Africa. The most parsimonious explanation for these findings is that west Eurasian ancestry entered southern Africa indirectly through eastern Africa.


Read more at: http://phys.org/news/2014-02-western-eurasian-genes-southern-african.html#jCp