Where does this road lead?

I was reading some news headlines the other day and saw a clip from the Washington Post.  It said:

“For the first time, scientists have grown an embryo that is part-pig, part-human. The experiment, described Thursday in the journal Cell, involves injecting human stem cells into the embryo of a pig, then implanting the embryo in the uterus of a sow …”

Is it just me, or does that sound ominous to anybody else?