Shared ancestries of Swedes, Estonians and western Finns

I am back with the mystery of commercial ancestry tests (while still preparing ancient Scandinavian samples), but I promise that this is the last time if don’t see amazing things happening, like FamilyTreeDna correcting their ideology.  I believe it will never happen.  Comparing two tests I have had possibility to check the 23andme's Ancestry Composition and  it is after the last spring’s revision better than what FtDna now can offer.  FtDna's results are so bad for Finns that I can't even make any reasonable review.  

Let's look at some basics.  There are three things which have a great impact to the quality of genetic ancestry analyses, reference sampling, method and authors understanding about history.  Authors must make compromises regarding reference samples, locations and amount of them and, what is even harder, they have to own some reasonable opinion about the timeline which they are looking for the ancestral idea.  Are they searching 500 or 5000 years back.  The big question is how the reference pack of each ethnic group can be connected to the desired time frame. 

In the case of Finnish and Scandinavian reference samples 23andme has not managed quite well.  My opinion is that in both cases they have found a unique sample set, but not an ancestral one.  Any sample set being unique enough can give unambiguous results, but not right ancestry in a desired time frame or in any time frame.  In the case of Ancestry Composition version two it is however possible to make some tricks to estimate real relations between national or ethnic groups by calculating all overlapping groupings and comparing three or more national/ethnic groups.  It is necessary to use comparison of several ethnic groups to form a big view instead of classifications made straight of reference samples.   This is necessary because the original grouping “Finnish” doesn’t mean Finnish in all cases, for example in Sweden, and in the same way “Scandinavian” doesn’t always mean Scandinavian in Finland and Estonia, for example those two cases.   I am going to do a test by using Scandinavian, Estonian and Western Finnish samples.

Sample set definitions

Scandinavians are a selected group of Ancestry Composition results from Southern Sweden, excluding Scandia, to Western Bothnia (Västerbotten).  They have published genealogical ancestries in their 23andme profiles without known Finnish ancestry.

Estonian group includes all for me now available results, excluding close relatives. There are samples from the north to the southeast and also from the west. 

Western Finnish group includes Finns from Finland Proper, Satakunta and Ostrobothnia without genealogically known Swedish ancestry.

Some basic statistics first.

Swedish samples

	Finnish	Scandinavian	British&Irish-French&German	Broadly North-E	East European	Broadly European	East Asian-Natvive Am.
Average	6,66	58,96	7,03	22,81	2,21	2,54	0,06
Median	7,3	55,8	6,25	22,9	1,45	1,65	0,05
Min	1,3	45,2	0,1	12,3	0	0	0
Max	9,9	75,1	16,3	38,5	7,7	9,8	0,2

Estonian samples

	Finnish	Scandinavian	British&Irish-French&German	Broadly North-E	East European	Broadly European	East Asian-Natvive Am.
Average	21,07	4,94	0,31	8,66	60,78	3,91	0,04
Median	19,9	3,8	0,3	8,6	49,7	3,9	0
Min	2,5	1,3	0	2,2	42,6	1,7	0
Max	43,5	10,4	0,9	16,7	90,6	5,9	0,2

Finnish samples

	Finnish	Scandinavian	British&Irish-French&German	Broadly North-E	East European	Broadly European	East Asian-Natvive Am.
Average	81,18	6,11	0,78	8,53	1,89	1,26	0,03
Median	81,4	5,7	0,5	8,3	1,3	0,7	0
Min	60,7	4,1	0	3,3	0	0	0
Max	90,4	9,8	2,4	15,9	4,9	3,8	0,1

Estonian samples look more heterogeneous than Finnish and Swedish samples, but it is only an illusion caused by the fact that they have not own reference pack.   They are split between Finnish and East European groupings.

Results, shared ancestry between Swedes, Estonians  and Western Finns.

Numbers are calculated by comparing individuals, not by ethnic averages.

Shared between Swedes and Finns:

		Finnish		Scandinavian		British&Irish-French&German			Broadly North-E		East European		Broadly European		East Asian-Natvive Am.
Shared ancestry	6,66		6,11		0,70		8,46	0,99		0,83		0,01		23,75

Total shared ancestry between Swedes and Western Finns is 23,75%

Shared between Estonians and Swedes:

Finnish

Scandinavian

British&Irish-French&German

Broadly North-E

East European

Broadly European

East Asian-Natvive Am.

Shared ancestry

5,99

4,94

0,28

8,58

2,21

1,76

0,02

23,79

Total shared ancestry between Swedes and Estonians is 23,79%

Shared between Estonians and Finns:

Finnish

Scandinavian

British&Irish-French&German

Broadly North-E

East European

Broadly European

East Asian-Natvive Am.

Shared ancestry

21,07

3,82

0,22

6,20

1,89

1,21

0,01

34,40

Total shared ancestry between Estonians and Western Finns is 34,40%

Those shared ancestries don't prove that Swedes, Estonians and Finns have just same named ancestors, only that they come from similar European ethnicities to the shared numbers.

 

There is only a small difference in the shared ancestry between Estonians and Swedes compared to the shared ancestry between Swedes and Western Finns, and both shared ancestries show similar figures for Finnish, Scandinavian and British&Irish-French&German ancestries.  It looks plausible that almost the whole shared ancestry with Swedes is inherited from a deeper history than 23andme assumes.