Genetic studies can't show anything for certain other than the current distribution of various base pair sequences (and that's well short of an exhaustive data set, since the samples amount to a tiny fraction of the 7 billion living humans), and here and there some fragments of a large handful of ancient individuals, and a small, even tiny, handful of prehistoric ones.
And they can't show geographic origins, and likely never will, due to that very dearth of early samples. Even an intelligent guess would require a complete chain of descent from, say, an early ancient person, down the family tree (unbroken or nearly unbroken line) to a living person.
I doubt that I could come up with the chance of DNA samples from any of my 16 great-great-grandparents, and I know where some of them are buried.
Reprise:
In her Plato Prehistorian: 10,000 to 5000 B.C. Myth, Religion, Archaeology, Mary Settegast reproduces a table which shows four runic character sets; a is Upper Paleolithic (found among the cave paintings), b is Indus Valley script, c is Greek (western branch), and d is the Scandinavian runic alphabet.
