As you said, not all studies can be done on humans, and some that could would be cost-prohibitive. My hope is that the ability to "print" organs will give us s

As you said, not all studies can be done on humans, and some that could would be cost-prohibitive. My hope is that the ability to "print" organs will give us some increased ability, though we would not be able to see impacts on the entire body. Something that has positive effects on one's heart is no good if it also makes one's head explode. There's still the concern of ethics with individual organs, though. How much of a person can you get without it becoming one? Is the idea of a "soul" reality? Tough questions. For now, mouse studies are imperfect but necessary. Like it or not, they may allow research that is not feasible on humans in terms of safety or cost. We probably need to continue them, albeit taking them with a grain of salt. In mice is worth something, mostly getting the next set of research funded.