Since someone brought up the idea that it must be of the devil, because God created male and female, I thought I would point out that the whole reason we are not to sin is so that the creation is not harmed.
Though such things as disease and mutation caused by man's actions may not all be specifically addressed in "the bible", (though there are verses which do address the subject overall) they essentially did not have the chance to be included in God's word to man, because man continually refused to hear and do.
The "tree of life" included God's continual oversight of and instruction about all things.
I am not saying that ALL disease and harmful mutation is the direct or indirect result of the actions of man coupled with our ignorance -but it would be extremely interesting to know the true statistics.
The fact is that things we do can and do cause intersexuality -though perhaps not in all cases.
Still -it would be interesting to know statistics concerning how man's actions may have even indirectly caused such in any case where it is not readily apparent.
It is said that God gave the creation over to futility in hope -so being cast out of the garden of Eden, as it were, could include God ceasing to maintain the creation -giving it over to whatever should befall it.
If God created a species after its kind male and female -and it was "good" -it does not mean that what he does cannot be made "not good".
We know that diet can affect health and even mutation -so the changes in dietary laws are also interesting in that regard. In Eden, they were vegetarian -if not Vegan. Afterward, God allowed all things to be eaten -though it's not as though some men needed to be told it was "ok".
Then -some things -and again -in the future, no flesh will be eaten.
Then there is the matter of manmade chemicals, medications, etc. Which can cause all sorts of "not good".
We often allow things we know will have harmful effects on each other, the environment, future generations. That is not to say that the devil didn't instigate the whole thing -but evil doesn't require much sustained effort or oversight.