BTW, and I'm no biolomogist but, from my understanding of the spread of both genuses that continental Europe would logically have the higher rate (which even in those who present those MOST neanderthal genes is minimal... I think under 3%) simply because neanderthals were predominant for a loooong time on the continent and that's where they first would have ecountered homosapiens (so where the most interbreeding would have occurred which was minimal anyway over the longest period of time) and I've never seen anything (thus far) stating that neanderthals managed to cross over water to Britain on their own (I could be completely wrong in that).
I believe the most activity of the neanderthal genus before they became extinct was in and around the area of modern day France.
So therefore, in my muddled understanding of the prehistory of man, it would make sense that any neanderthal genes only made it to the British Isles within homosapiens who had interbred with neanderthals and their generational offspring are the ones who carried it across the channel.
I am only a (VERY) casual student of this crap so I am likely... well full of crap... but it is very interesting stuff.
The new findings about how aboriginal North Americans arrived though are even more interesting.
Even MORE interesting than that are how the Pacific Island and Australian aborigines made their crossings.
We are all one people.