Great Britain has the harshest laws regarding incest.
You can't even marry someone that has your last name, even if you're not really blood related.
Its so much the deteriations (as far as I know thats the same if you have kids with your sister or with anyone) its the fact that you have a hugely increased chance of both having and thereby passing onto your children recessive genes that are usually 'covered' by the normal dominate genes. These can cause anything from say a slightly larger lower jaw (as seen in some of the European Royal Families in the middle ages) to full-out genetic disorders.There's scientifical proof that breeding with someone too closely related to you causes defects and deteriation in DNA. They say it's how the Mammoths died out now.
So out of concern for having healthy human babies, I severely look down upon having a romantic relationship with anyone related enough that you know they're related to you.
oh god wtf no.
Never thought I'd hear you say that......:CIsee:
you're so funny :CAbove:
no, not really.:CCry2:
yeah, not really.
AHAHAHA Echodragon pwned masq.... Lul
Yeah that was epic. I think I came.