Actually for the first time I'm seeing a scripture that really spell it out that it's a sin, yah i know that the bible forbids it, relatives to marry but I don't just Know were it is in the bible up untill now.
Well due to the research it is scientifically wrong and not advisable plus the scripture also condemns the act, it's totally forbidden and so God actually spells it out in the book of Leviticus as read to us.
So the book of Leviticus 18 from 6-18 is a long scripture, that specifically outlined all of the relatives that a man or woman must not come across wether from the father or mother kinsmen or kinswoman
None of you shall approach to any that is near of kin to him, to uncover their nakedness: I am the LORD.
Leviticus:18:6
But you see in today's world, every body is acting confused, doing all sort of wickedness, these acts are rapidly becoming a norm in our society like nothing is wrong, doing all forbidden acts and turning deaf ears to the warnings of the lord or what science have discovered.
Just like the scientist have found out the adverse effect of all these which is enough warning for people to refrain from such acts you see people paying deaf ears to these warnings at the end of the day its the children that will suffer the consequences....