I have a silkie roo that is no problem. Now, if I pick up one of the girls or a baby is screaming he will come running to see what is going on, but a firm "Ricky NO" and he stops and waits. I have to agree it is somewhat genetics. I got Ricky and a hen from the feed store. They were already full grown and I know they had been in a smallish cage for 3 months. (it took me that long before I could actually commit to "buying" a chicken!!) When I got them home I had to literally dump them out of the cage to come outside. I don't think they had ever been on grass before. The hen was scared stiff. It took her about 30 mins to move. Then she ran into a medium size stick on the ground and had no clue how to get around it. I had to go move the stick for her. We now have a mix herd running around and all of his sons have been just like him. I am in no way afraid of them or ever fear they would attack someone. I for one was scared to death of chickens. I actually couldn't breathe when I was around them. Because of this herd, I am much better off now.
Good Luck!
Good Luck!