I just saw this thread and can shed some light on this, I think.

It has been decided that all but "1" sibling of the orginal 7 children born to my grandparent inherited this genetic chemical inbalance. Call it genetic or chemical, it is still inherited. Then depending on what triggers the individual they go into their own conditions.

My grandfather quite life at 50 and never worked another day in his life. To make ends meet, my grama took in boarders. Grampa had what mom remembers as his "spells".

He went out to the family cottage at the lake and stayed there about 4 years. Seeing no one and doing nothing. He was not capable at that point. Grama went out once a week for dirty clothes, to deliver food, etc.

I have several cousins and "1" uncle who have received electric shock therapy. Most all of the cousins have one form or another of this crap. While all my mom's siblings have since passed away, through discussions with therapists, it has been decided that all the kids had it.

There is no question in my mind that the genetic connection exists. I am the product of that connection