My new-world (before there was an America) bloodline traces back to 1638 with Joseph Loomis. Before that to the eastern areas of England. My mother is Pennsylvania Dutch, German. So, out of curiosity I had one of those DNA tests done. Not surprisingly I am of European descent... 99.7% actually and most of that is north-western Europe, Scandinavia and the British Isles with traces of Neanderthal blood, a people who lived in north-western Europe over a hundred thousand years ago.
