Most bananas propagate asexually and multiply via small bulbs that grow out of the plant's rhizome underground called the corm. Thus they are basically clones of the parent plant.
However, wandering through the rain forest in Brazil, I came across these delightful pink bananas, which open by themselves as they ripen and resemble a little boy's penis, and discovered they have very hard black seeds inside. I imagine these can then be grown and will not be clones.