Genetic inheritance is different to the social construct of race ("black","white" etc). Bloodline is best avoided as a concept where humans are concerned, becau

Genetic inheritance is different to the social construct of race ("black","white" etc). Bloodline is best avoided as a concept where humans are concerned, because the human gene pool was and is highly mobile. "Racial purity" is an idiot concept, and to the extent it has been attempted in humans, as with dogs it mostly leads to deformities and genetic diseases. (That Proclaimers song - "... and I would walk 500 miles" - turns out to be an order-of-magnitude underestimate of how far the 99th percentile will walk to get laid - and on a timescale of centuries/millennia, it's the 99th percentile that matters). And remember that in the US (and, for example, South Africa), that social construct extended to become a _legal_ construct used to discriminate against those designated as black. Most of Europe doesn't share that unhappy recent history (although we have our own, of course), it's hard to appreciate just how much more contentious it is in the US than Europe.