Can African Ancestry really tell which African country an African American's ancestry is from? (find, world)

[Jonathan Morningstar]

Let's say an African American has a DNA match in Nigeria. Does that actually mean the ancestry is Nigerian? What if the ancestors where in Ghana or Sierra Leone 300yrs ago?

Isn't the African database too small?

Originally Posted by Jonathan Morningstar

Let's say an African American has a DNA match in Nigeria. Does that actually mean the ancestry is Nigerian? What if the ancestors where in Ghana or Sierra Leone 300yrs ago?

Isn't the African database too small?

Ususally this type of test does either the Paternal line (Y-DNA) or the Maternal line (mtDNA). It just shows the likely origin of each haplogroup.

So for instance if you go back, as you say, 300 years you will have approximately 10 generations (30 years each). That would give you approximately 1000 individual ancestors. The above tests only show you one ancestor for each line (Paternal and Maternal) - where your Y-chromosome came from and where your mtDNA came from. This is based on the statistical measure of those markers being most prevelant for those areas - say for instance Nigeria.

So as an example someone could look totally 'white' yet have a Y-Chromosome that is most likely from Nigeria because somewhere (most likely far back) he had an ancestor that came from this region - a 'black' man.

All other genetic info needs to be tested for (Autosomal DNA) to account for all the other individuals in your ancestry (the remaining 998).

As far as the database being to small - I am not sure. It would not be hard to find out.

Here is some info Genealogical DNA test - Wikipedia, the free encyclopedia

Hope that helps!

[mlungisi]

AfricanAncestry claims to have the largest database of mtDNA and yDNA as far as can they tell I'm guessing they can tell that you have basically distant cousins in what ever modern country in Africa today those cousins are Nigerian for example now you could find out if they migrated from another place by studying that matching or close groups history usually people did not move to far so if they say Yoruba mtDNA, they probably were in Nigeria not Sierra Leone likewise if they were Temne-Mende they would not be Nigerian

[brownbagg]

no, the tribe and countries are too close and intermingle, so if you west coast, your lucky

[SobreTodo]

Originally Posted by Jonathan Morningstar

Let's say an African American has a DNA match in Nigeria. Does that actually mean the ancestry is Nigerian? What if the ancestors where in Ghana or Sierra Leone 300yrs ago?

Isn't the African database too small?

Yes and no!

Usually tribes and groups, but you have to use relative match finders to help infer the connections and antecedents.

[linana75]

We should say ethnic group in Africa rather than African country.
I'm telling you because you can come from the same country but not having the same ethny and that makes all the difference.
Now to answer your question we can try to identify which etnic group an african american belongs to but it won't be a certitude.

[PA2UK]

This topic is from over 2 years ago but with that in mind, I'm not entirely sure what was meant by "a DNA match in Nigeria". Are we talking about an ethnicity percentage match? Or a cousin match to an individual in Nigeria? Autosomal? yDNA? mtDNA?

Most autosomal DNA tests will break African ethnic percentage results down into regions of Africa. If someone has ancestors from a mix of regions, it will likely be reflected in the results, with percentages in different regions. But what the results tell you is just that your DNA matches the sample group from that region. It does not tell you where specific ancestors were 100 years ago vs 300 years ago. If someone has recent ancestors from Nigeria but earlier ancestors from Ghana, the ethnic percentage results will depend entirely on their genetic make up and which sample group they most closely match - it may be one or the other or both. How big the sample group is depends on the DNA company you tested with.

If we're talking about a cousin match to someone in Nigeria, then no, it does not necessarily mean your ancestry was from Nigeria. That individual could have been the first generation born in Nigeria for all you know.

[thriftylefty]

It has been said that two Africans from the same tribe have more genetic diversity between them than two randomly selected people in the world.