I don't know so much about genetics but I do know that Turkish people at least in European part of the country are pretty much Greeks and yeah it's also true everyone mixes with neighbouring population. That's a no brainer.
Honestly I don't know so much about Sri Lankan genetics. I guess I look like any other South Asian and often get confused for Indian but I am guessing SL population is also mixed. Even though it's an island, it was connected to major trade routes since 2500 years and was a part of maritime silk road.