What is SAPDA, and how is it different?
In the following, I will go through various aspects of my results and discuss them in depth.
Most of my ancestry is European, and the high percentage of West Eurasian DNA is as expected. In every testing company analysis, my highest European region is Scandinavia, followed by the British Isles. My Finnish estimate varies, peaking at 10% (FTDNA myOrigins v1.0) and 10.5% (MyHeritage upload). SAPDA does not go into subregions, however.
East Asia and Siberia
SAPDA is able to pinpoint a substantial genetic contribution from East Asia and Siberia/the Americas (3.6% + 6.9% = 10.5% in total). Some Siberian and East Asian is expected, due to my Forest Finn and Sami ancestors (see e.g. this blog post); however, my score is unexpectedly high. My East Eurasian lies within the Northwest European average range, but my Siberian-American is distinctly elevated, even relative to Finns (compare references here). Besides Forest Finns and Sami, some of my Siberian and East Asian DNA might come from Romani, Malagasy, or Taíno ancestors, or from my Russian lineage, or from ancestors who were part of the Mongol and/or Turkic migrations into Europe – if not several (or all) of the above.
SAPDA separates admixture into “Ancestral” (more recent) and “Deep Ancestral” (more ancient) levels, based on analysis of older versus more recent shared mutations. Interestingly, my Ancestral graphs above show less West Eurasian and more East Asian and Siberian than the Deep Ancestral graphs. Dilawer Khan himself, commenting on similar results, has stated that “The slight increase in E Eurasian admixture in the more recent past is unsurprising for Europeans in light of the migrations west by Turkic and Iron Age Steppe peoples.” In other words, this admixture is real, and may be relatively recent.
East Asian DNA also shows up for me in testing company results. In an earlier version of 23andMe’s Ancestry Composition, I had 0.1% Broadly East Asian. In FTDNA’s myOrigins, I have <1% Northeast Asian. This Asian admixture (read by FTDNA as a combination of Northeast and Southeast Asian) is also carried by my father and his father, which is the line where my Sami ancestry comes in.
Although I have some African (West African and Malagasy) ancestors born in the 1600s and early 1700s, recombination seems to have watered down my African genetic component to nearly zero, which is consistent with my results from other analyses, including my testing company results. Interestingly, however, SAPDA shows that I am homozygous for (having two copies of) 23 East African signature alleles in a cluster on chromosome 16, which makes it very likely that I do indeed have real East African DNA (according to Dilawer Khan, having two copies of an allele “would have a much lower probabllity of match due to a random event”). East African does show up in my Deep Ancestral graphs above, at 0.50% in admixture proportions and 0.40% in GSI.
Chromosome painting showing the locations where I have one or two copies of alleles defined as East African. SAPDA provides such chromosome paintings for each geographical region. Mousing over the red and blue marker gives additional specific information about the individual locations.
Visualisation of all my East African alleles and their frequencies in populations. Some of them seem to have a 0% frequency outside Africa, and are thus presumably informative of African ancestry. Similar visualisations are given for all the regions.
I know of one (possible) East African ancestor on my mother’s side – the Ethiopian woman Qirwerne who lived in the 1100s. If David Hughes' genealogical theory is correct (see previous link), my mother descends from Qirwerne through 8 known lines. My father is also possibly descended from Qirwerne, and if so, it would provide one possible explanation for why I am homozygous for the East African alleles.
Another possible explanation is that the East African DNA comes from my parents’ Romani ancestors, some of whom were probably originally Siddi people, i.e. descendants of Bantu-speaking East Africans who came to India as merchants, sailors, indentured servants, slaves, and mercenaries beginning in the 7th century AD. Romani scholar Ian Hancock argues that “From the very beginning, the [Romani] population has been a composite one […] Evidence points to Dravidian, Scythian, and even East African (Siddhi) input into the early mix of militia and camp followers” (my emphasis).
East African DNA also shows up for me in testing company results. In an earlier version of 23andMe’s Ancestry Composition, I had <0.1% East African (on chromosome 6). GEDmatch analysis showed this segment to be inherited from my mother.
One of SAPDA’s drawbacks is that it does not report South Asia (the Indian subcontinent) as a separate category; it seems to be read as part of the East Eurasian category. Another calculator designed by Dilawer Khan (and with a similar purpose as SAPDA), the Eurasia K5, is able to pinpoint my South Eurasian ancestry at 1.0%. This can be explained as coming from my Romani lineage, in which South Asian DNA has been mixing with West Asian DNA since the 1000s and with European DNA since the 1200s. The low South Eurasian percentage is as expected, since the Scandinavian Romani people are a highly European-admixed population. Viewed in the context of my total amount of Scandinavian Romani ancestry (1/8 + 1/64 = 14.06%), my result is consistent with the testing company results and GEDmatch results of other people of Norwegian and Swedish Romani descent.
A person with a Romani great-great-grandmother got rather similar results to me in SAPDA, except that he had elevated East African (5% admixture, and 1.50%/1.60% in GSI Deep Ancestral/Ancestral).
I'm very happy with SAPDA. I especially like the fact that it shows (in the report's own words) "graphical evidence of genes shared with other populations in support of admixture percentage calculations". More generally, SAPDA gives support and plausible context to a number of trace regions I've been receiving at testing companies as well as from calculators on GEDmatch and elsewhere. As mentioned, the smaller percentages I get from SAPDA are consistent with the smaller trace regions I've been getting at 23andMe and FTDNA. And while my non-European percentages at SAPDA are higher than I expected, they do make sense from the historical context, and the Asian percentage levels are actually not that far off some of my other third-party results. All in all, I am now considering SAPDA to be probably the most accurate estimate of my continental-level ancient and semi-ancient ancestry, and yes, that is high praise.
I find SAPDA to be a very good analysis for those (like me) who are specifically interested in their continental ancestry in an ancient and semi-ancient timeframe. The only drawback is the lack of certain regions, such as South Asia. Although the report is a bit technical and demands some basic knowledge of genetics from the user, it has better structure and more features and interactivity than any other ancient calculator I have tried. SAPDA promises no more than it delivers, and it delivers exactly what it promises.