[jla]

I'm not a geneticist but am capable of simple elimination.
Since you're so sure it wasn't northern Europeans who are responsible then who is?

[Bohemund]

I'm not a geneticist but am capable of simple elimination. Since you're so sure it wasn't northern Europeans who are responsible then who is?

Why are you so sure that it was introduced into the native Irish population by interlopers, rather than arising locally? The simplest explanations are usually correct.