Response to Karrie-Ann’s on incest.

I found this topic interesting because different people have different opinions about this topic. I am not saying that incest in right buy many years ago like in Egypt people would sleep or marry a family member. So why do the society frown upon incest? I think it’s because of science for example if you had sex with you brother and you had a child the child would most probably come out deformed because of the parent share the same DNA. It’s because of society that people’s views on incest have changed. What do you think?