This is the last post in the series covering free admixture analysis tools and how sub-Saharan admixtures are calculated and reported. You can read the full series of posts here: http://genealogyadventures.net/tag/african-dna/
The last Gedmatch DNA admixture analysis test I’ve run is the EthioHelix K10 Africa Only test. It is a very interesting test indeed.
The developer of this test has front-loaded an important caveat on the test page: Results are currently only meaningful for persons who are 100% African. Ironically, considering I’m not 100% African, EthioHelix best represents the geographical spread of my African DNA of all the Gedmatch tests I’ve explored.
EthioHelix K10 Africa Only Admixture Proportions
So no, the proportional weightings aren’t quite correct. However, taken as a representational concept, this test shows that many regions of Africa have contributed to my genetic makeup.
One additional EthioHelix test I highly recommend exploring is the Admixture Proportions by Chromosome test.
The thing that fascinates me about this test (which can be run for any of the admixture tests available on Gedmatch) is the peaks for each region in my chromosomal spread. I hold my hand up to say I haven’t grasped the significance of the peaks on specific chromosomes. I’m not a geneticist. I just find it amazing that the admixtures I’ve inherited influence some chromosomes and not others. I have some reading to do on this!
If you’re African-American, it’s definitely worth using this analysis option with the HarappaWorld test. Here’s my results:
One of my questions, using the Harappa test above as an example, is why some peoples/regions contribute to almost all of my chromosomes (i.e. Northeast European, Mediterranean and Central Asian/Caucasian) while others are only connected to a handful of chromosomes (i.e. Southeast Asian and Siberian). Does this mean I have fewer ancestors that were Southeast Asian and Siberian? Does time influence a relationship between admixtures and chromosomes? There are so many questions!
So what are my overall takeaways?
It’s definitely a test worth exploring the Gedmatch tests to see which regions of Africa have contributed to your own admixtures. I think that’s the best way to approach such tests. I wouldn’t concentrate too much on the percentages.
Overall, I’d say there is a distinct need in the marketplace for the development of an admixture analysis tool for African and African-descended peoples. Such a test needs to be developed by a team who have a deep and thorough knowledge of African DNA – especially how African admixtures have developed over the eons and how to give a proper weighting to certain aspects of African admixtures. in other words, develop an African-focused admixture analysis tool that is as sophisticated and as refined as comparable tests for European and Eurasian peoples.
In the next post, I’ll be writing about the true genius of Gedmatch: locating long lost relations who have used different DNA testing services.