As far as I know, I'm totally northern/western European:
German: About 3/8
Irish: About 1/4
Danish: About 1/8
The remaining 1/4 is some mixture of English, Scottish, Welsh, Dutch, and French.
In other words I'm a major white American mutt.
Dick is about 8.25" x 6.25" mean measurements.
I saw my dad's soft dick in the locker-room once when I was about 13, and it was way smaller than mine, so unless he's a major grower, I know that's not where I got the genes. I remember seeing my grandpa (on mom's side) peeing once when I was little, and I remember it was pretty big, so I think that is where I get it from. He is mostly German. This would be consistent with a lot of the German dicks I've seen in porn being of similar size and shape to mine. I don't think that Germans are necessarily especially hung, but the big ones among them seem to look a lot like mine.