Recently I was a little obsessed with finding the origin of my fetish, and had a list of possible causes and how they might be confirmed or eliminated. On the list was "genetics", and next to it I wrote "impossible to confirm", simply because I refuse to let my family know I have any interest in the subject. Not that I think they'll judge me, I just don't feel it would do me any good to tell them.

Now, could I imagine my parents or anyone else in my family engaging in kinky activities behind closed doors? I wouldn't put it past them, because I know that such tendancies can manifest in all sorts of people. But to me it'll always be a mystery. Or at least that's how I'd like it to be.

As to whether the preference for BDSM might be genetic, I think it's entirely possible. After all, I can't think of any other way I could have gotten it.