I can't speak for others, but I recall being taught that there are three situations that command a Jew to lay down one's life: 1) Threatened with death if one does not disavow Judaism and our G-D. 2) Threatened with death if one does not murder another. 3) Threatened with death if one does not commit an act of sexual impropriety(like rape, beastiality, incest, etc).What if instead of telling me, you pointed a gun to my head and told me to shoot someone else? Is that morally equivalent?
Otherwise, it is a Jew's duty to shed the rest of the Torah, at least temporarily, to save a life, be it his or another's.