Is the kink always there or was it just there in the photo? Let him crawl through your hand and feel for anything abnormal. I'm no expert but I happen to have a caramel glow and caramels can have some issues with kinking so I've done a lot of reading on the matter. For them, yes it can be genetic. I'm not really sure though about normals? I would assume that any kind of deformity can be passed down to their offspring if it wasn't from an injury.