About 2 years ago I was watching a documentary about china-to-america adoptions on japanese television. While the point was never explicitly raised, the viewer could not help but notice that most or all of the children up for adoption - no interested chinese parents having being found - were, and there's no nice way to say this, quite physically unattractive, developmentally challenged, or both.
The program showed American couples arriving to claim their new family member and I was struck by how unwitting they seemed. I got the impression they simply did not have enough experience with asian children to realise that their adoptive child had, to put it brutally, a pretty poor genotype, with a host of physical and behavioural ramifications.