Researchers in South Korea and New York have independently succeeded in using embryo cloning to produce stem cells genetically matched to specific patients:
Stem Cell BreakthroughThe article compares and contrasts embryo cloning with IPS (induced pluripotent stem) cells as a method of creating stem cells. In the latter process, the “clock” of adult cells is “turned back” to enable them to be reprogrammed into whatever types of cells are needed. Some experts believe embryonic stem cells are superior to IPS cells for various reasons; however, embryonic cloning is controversial and limited by the availability of human ova. Researchers, as one would expect, state emphatically that they have no plans to grow human individuals from cloned embryos.
This process sounds much less Frankenstein-like than the artificial organ production method in vintage science fiction such as Heinlein’s future worlds. In many of those novels, an entire, full-grown duplicate body is grown as a source of replacement organs. In one of Heinlein’s Lazarus Long books, Lazarus saves his mother’s life and brings her from the twentieth century into the distant future without disturbing the time stream, by substituting a cloned double of her at the instant of her recorded death. This doppelganger has never had consciousness; it’s physically adult but never mentally awakened, basically a mannequin made of flesh. Stopping to reflect on this incident might arouse qualms about the ethics of creating a fully formed human body, even a mindless one, solely for the purpose of killing it.
It seems distinctly less ethically problematic, for therapeutic purposes, to grow particular tissues and organs in vitro rather than produce a whole body to harvest organs from. More convenient and versatile, less expensive, and probably simpler, too. One exception might be—if such a procedure ever becomes possible—brain transplants. An aging or terminally ill rich person might have a youthful body grown in a lab and have his or her brain transferred into it. The ethical problem of creating a complete human body (even though never intended to become a conscious individual) simply to dismantle it for parts wouldn’t apply if the new body is designed as the vehicle for a fresh lease on life.
Margaret L. Carter
Carter's Crypt
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