Here is the map of East European admixture. I would need more data from East Germany, Czechia, Austria, Slovenia, Estonia, northern Russia, Moldova, the Volga-Ural region, the Caucasus and Turkey to work out the gradients.
Here are my Czech samples, but most of them are from Northeastern Moravia where my 23andme matches come from. I would describe ancestry of this region as more Slavic than most of the country. In last 500 years it was under clear genetic influence of two foreign groups of peoples. First are Sudeten Germans (almost everyone I know from there has some more or less distant German in his/her family tree). From 16th century it was also influenced by Vlachs, highland pastoralists with original Balkan-like and East Slavic-like culture. They originated in Balkan highlands (Northern Greece, Bulgaria, Romania) where are now called Aromuns, but they mixed with aborigines through their journey along Carpathian Mountains. Their influence is evident from culture of eastern Moravia, linguistics (eastern Slavic and Romanian-like dialect), average physical appearance (dinaroid or „east slavic“ facial structure uncommon in Bohemians or other Moravians, higher stature, more frequent darker skin) and haplogroups (I2a1b, J2, E, R1a). But I think Vlachs were in fact more East Slavic than Balkanic autosomally.
Please interpret my results as Moravian and not generally Czech, I think Bohemians would score different.
[TABLE="width: 657"]
[TR]
[TD][/TD]
[TD]CZ1[/TD]
[TD]CZ2[/TD]
[TD]CZ3[/TD]
[TD]CZ4[/TD]
[TD]CZ5[/TD]
[TD]CZ6[/TD]
[TD]CZ7[/TD]
[TD]AVERAGE[/TD]
[/TR]
[TR]
[TD]EASTERN EUROPEAN[/TD]
[TD="align: right"]47.5[/TD]
[TD="align: right"]64.7[/TD]
[TD="align: right"]43.9[/TD]
[TD="align: right"]47.4[/TD]
[TD="align: right"]52.9[/TD]
[TD="align: right"]69.1[/TD]
[TD="align: right"]44.8[/TD]
[TD="align: right"]52.9[/TD]
[/TR]
[TR]
[TD]N.W. EUROPAN[/TD]
[TD="align: right"]16.7[/TD]
[TD="align: right"]10.2[/TD]
[TD="align: right"]37.3[/TD]
[TD="align: right"]25.9[/TD]
[TD="align: right"]32.4[/TD]
[TD="align: right"]12.8[/TD]
[TD="align: right"]16.2[/TD]
[TD="align: right"]21.6[/TD]
[/TR]
[TR]
[TD]French+German[/TD]
[TD="align: right"]2.2[/TD]
[TD="align: right"]1.7[/TD]
[TD="align: right"]9.6[/TD]
[TD="align: right"]5.6[/TD]
[TD="align: right"]8.8[/TD]
[TD="align: right"]0[/TD]
[TD="align: right"]0[/TD]
[TD="align: right"]4.0[/TD]
[/TR]
[TR]
[TD]Scandinavian[/TD]
[TD="align: right"]1.5[/TD]
[TD="align: right"]1.6[/TD]
[TD="align: right"]1.9[/TD]
[TD="align: right"]0[/TD]
[TD="align: right"]0[/TD]
[TD="align: right"]3.1[/TD]
[TD="align: right"]0[/TD]
[TD="align: right"]1.2[/TD]
[/TR]
[TR]
[TD]British+Irish[/TD]
[TD="align: right"]0.5[/TD]
[TD="align: right"]0.2[/TD]
[TD="align: right"]2.6[/TD]
[TD="align: right"]0[/TD]
[TD="align: right"]2.4[/TD]
[TD="align: right"]0[/TD]
[TD="align: right"]0[/TD]
[TD="align: right"]0.8[/TD]
[/TR]
[TR]
[TD]Broadly NWE[/TD]
[TD="align: right"]12.6[/TD]
[TD="align: right"]6.8[/TD]
[TD="align: right"]23.1[/TD]
[TD="align: right"]20.4[/TD]
[TD="align: right"]21.2[/TD]
[TD="align: right"]9.7[/TD]
[TD="align: right"]16[/TD]
[TD="align: right"]15.7[/TD]
[/TR]
[TR]
[TD]SOUTHERN EUROPEAN[/TD]
[TD="align: right"]16[/TD]
[TD="align: right"]17.8[/TD]
[TD="align: right"]8.2[/TD]
[TD="align: right"]14.2[/TD]
[TD="align: right"]3.9[/TD]
[TD="align: right"]9[/TD]
[TD="align: right"]16.5[/TD]
[TD="align: right"]12.2[/TD]
[/TR]
[TR]
[TD]Balkan[/TD]
[TD="align: right"]14.3[/TD]
[TD="align: right"]14.2[/TD]
[TD="align: right"]7.5[/TD]
[TD="align: right"]11.9[/TD]
[TD="align: right"]0.6[/TD]
[TD="align: right"]7.1[/TD]
[TD="align: right"]7.9[/TD]
[TD="align: right"]9.1[/TD]
[/TR]
[TR]
[TD]Broadly Southern E.[/TD]
[TD="align: right"]1.3[/TD]
[TD="align: right"]3.6[/TD]
[TD="align: right"]0.7[/TD]
[TD="align: right"]2.3[/TD]
[TD="align: right"]0.8[/TD]
[TD="align: right"]1.8[/TD]
[TD="align: right"]8.6[/TD]
[TD="align: right"]2.7[/TD]
[/TR]
[TR]
[TD]BROADLY EUROPEAN[/TD]
[TD="align: right"]19.7[/TD]
[TD="align: right"]7.3[/TD]
[TD="align: right"]10.4[/TD]
[TD="align: right"]12.5[/TD]
[TD="align: right"]10.7[/TD]
[TD="align: right"]9[/TD]
[TD="align: right"]20[/TD]
[TD="align: right"]12.8[/TD]
[/TR]
[/TABLE]
Note that the results between individuals are quite different. All of the samples have of course 4 grandparents from Czechia.
CZ1 - Me, Northeastern Moravian/Silesian (Slavic or Wallachian surname)
CZ2 - Northeastern Moravian/Silesian (Wallachian surname)
CZ3 - Northeastern Moravian/Silesian (German surname)
CZ4 - Mixed Southern and Northern Moravian (unknown surname)
CZ5 - Mixed Bohemian and Moravian (common Czech surname)
CZ6 - Moravian (Slavic surname)
CZ7 - Silesian from around Polish border (unknown surname)