It would be interesting and you know I will read those references! I had read that about Genghis Khan. But his genes are likely so diluted it wouldn't make a difference. I think, behind the first few generations (fortunately) everyone is such a hybrid that it would be hard to sort. Even in cultures that seem to be homogeneous, if you look at migration patterns going back hundreds and thousands of years, you will see that we are all mongrels. I have to admit that I do look back. Vikings in Russia. Greeks in Sicily. Persians in Greece. Mongols in China.
I think I'll leave off now and read your references :)