I enjoy writing about a variety of people--young, old, in between. Children, teens and adults. Normal and disabled (although I think calling them disabled is a disservice). And yet genres tend to point to one group of people and say "this is what we write about."
One of my books has a teenage boy taking care of a baby (albeit reluctantly, at first) and another book that has two protagonists--an eleven year old girl and her father. I have a book that includes (as a minor character) an autistic child. I have a woman running from an ex-boyfriend and another woman who's an alcoholic. My characters have (gasp!) families and connections outside their own genre-age-group.
It may seem odd, but I refuse to confine myself to one aspect of the human spectrum. I see no reason to. Life doesn't take place in a vacuum. Having a soap-opera cast in a book (all young and beautiful, smart and talented) doesn't appeal to me as a reader, so why should I write it?
I write about the flaws, the joys, the twistedness of life. I intend to keep doing it, because without a varied cast of characters life would be stupidly boring, no matter what the plotline.
Call me a genre-buster if you wish.