Comment: Lighten up Dan.  (Oops...my bad...you are Jon Caldera....the cheap, generic version of Dan Caplis who was the cheap, generic version of Mike Rosen).  It is sci-fi.  We are talking about an alien dies and then can regenerate, ---and you are caught up in the proposition that in the regeneration they can change genders?  I'm not a fan of Dr. Who (although I do like sci-fi) but I'm curious, do they show the good Dr.'s the genitals?  Are they pertinent to the story?  Does the Dr. shoot lasers from his penis?  If not, then what difference does it make if the Dr. is packing a pee-pee or a po-po?