You guys read anything about CRISPR-cas9? It's fascinating stuff! Basically, it stems from a pair of scientists finding a new, revolutionary way to perform genetic modifications. It is so precise that it is probably more accurate to talk about genetic editing. Previous methods on genetic modification were coarse, not precise, and often led to unwanted mutations. That is no longer the case with this method, and apparently it is also a technique quite easy to use. For good or bad.
Up until now, the practical results aren't things that necessarily would make you raise your eyebrows; a new breed of genuine miniature pigs (I wouldn't personally mind one of those btw), a breed of dogs with extra strong muscles combined with superior stamina, and cows without horns. However, this is only the very tip of the iceberg of what is actually now able to be done, and not only on animals. For instance, from what I understand it wouldn't be very hard to reproduce the traits in those dogs on humans... That, then, raises the moral and ethical question - where do we draw the line?