I don't care for it, but you can tell when people are from the US or more european nations. Large parts of the world still think uncle/aunt isn't close enough in blood relation to be an issue.
Though, as far as genetically is concerned, I think it's "second cousin" is technically distant enough. When I was in college there was a paper done on the subject, and iirc the chance of a genetic issue is 2%~ at that distance which is within margin for -any- child.
Blech though.
Of course, the best thing you can do for you children genetically is mix nationality. Kinda sad so much of the world has problems with mixed 'race' couples despite genetically being the ideal mix- genetically.