The situational ethics theory was first postulated during the 1960's by Joseph Fletcher. It was intended to be a middle ground position in the Christian world of ethics between antinomianism and legalism. Antinomianism says there is no law—everything is relative to the moment and should be decided in a spontaneous fashion with man’s will as the source of truth. Legalism has a set of predetermined and different laws for every decision-making situation. Fletcher’s ethical theory is based on only one absolute law, which when applied properly, handles every situation. Fletcher posits his situational absolutism with its one law for everything by saying we must enter every situation with only one moral weapon—the law of agape love. According to Fletcher, Jesus summed up the Mosaic law and the Ten Commandments in one word—love. Therefore, there are no commandments which may not be broken in some situation for love’s sake. Every law is breakable by love.
Situation Ethics instructs us to love. It is a theory concerned with humans (one of the four Ps is Personalism). Therefore situationists would be more than happy to use animals to grow organs or pharmaceuticals. The real question with these therapies is: is it Pragmatic, does genetic 'pharming' work? There is good evidence to suggest they do work very successfully, so Situation Ethics would support them.
What about human genetic engineering? Gene therapies that are somatic (in one person's body [soma]) would doubtless be seen as a loving alternative to letting someone suffer and die. Germ-line therapies are more problematic, as they may affect many future generations, and Situation Ethics is teleological, concerned with the ends. However, situation ethics is Relativist, relativism which means that if the it may be too risky as a general rule to make changes to a germ-line, but situation ethics is happy to 'throw