How close is far enough? (Incest)

[TheTROLL]

I vaguely recollect learning about this in a Family Law course as part of my law degree (this was early on, before I stopped attending lectures).

The legal term in the UK is consanguinity .

As I remember, 1st cousins are allowed to marry here, but uncles/nieces (aunts/nephews) are not. But the uncles/nieces (aunts/nephews) ARE allowed to sleep together (and not in the Lexington Brian/Olivia way). That sounds WAY too close genetically to be a good idea, so I'm now thinking I could be wrong, will go look it up...

[TheTROLL]

Yup, you can marry your cousin here, but not in most of the US, it seems. Can find anything definitive on the uncle/niece (aunt/nephew) thing either way.

The social stigma of it outweighs the benefits given the amount of non-incest possibilities for relationships