User blog comment:It's Good to be the Queen/Pendragon Family Reunion/@comment-5102537-20121014172327/@comment-5102537-20121014193217

Scarlet, the mental illness of Uther's father was mentioned in a deleted scene only. We don't know how relevant the deleted scenes are, given that the episode only dealt with Uther's madness caused by the mandrake root.

I wouldn't go down the route of a genetical failure in the Pendragon family...

Uther had his mental breakdown after and due to Morgana's betrayal, it wasn't such a mental disease but shock and deep depression, an emotional issue.

Locking Morgana up or grabbing her throat which happened only once and never again whereas Uther showed her nothing but love and respect afterwards, could never make her insane and so hatred-filled. And it wasn't Merlin either. To get so mad and crazy up to that extent there is a lot more necessary. Something must have happened in the missing year with Morgause but nothing whatsoever what has happened on the show in Camelot could have ever made Morgana or anyone what she has become. It is Morgana who is responsible, nobody else. She suffers from a serious mental disease and it must have happened when she went missing at the end of season two.

@It's good To be Queen, we don't know if Igraine and Uther had already been married when Morgana was conceived. It's possible but actually, according to what was shown about Uther's relationship with Igraine and his feelings for her, unlikely. I think we will never get an answer to it, though.