Last week the BBC reported that scientists in the United States are trying to grow human organs inside pigs

Last week the BBC reported that:

Scientists in the United States are trying to grow human organs inside pigs. They have injected human stem cells into pig embryos to produce human-pig embryos known as chimeras. The embryos are part of research aimed at overcoming the worldwide shortage of transplant organs. The team from University of California, Davis says they should look and behave like normal pigs except that one organ will be composed of human cells. The human-pig chimeric embryos are being allowed to develop in the sows for 28 days before the pregnancies are terminated and the tissue removed for analysis.

Distinctions are important

As often with reports by the mainstream media on complex scientific or ethical stories, there were some inaccuracies in the BBC's report. Dr Anthony McCarthy, SPUC's resident bioethicist, explains:

"The story concerning attempts to grow human organs inside pigs is, predictably, generating interest. As with all such stories, we need to be careful to make distinctions before jumping to ethical conclusions. What is being proposed is not the creation of a new embryo but rather the introduction into a pig embryo of human induced pluripotent (iPS) stem cells derived from adult cells. None of this involves the creation or destruction of human embryos and so is not condemnable as constituting the destruction of new human lives. Nor does it involve the use of human material such as human sperm or eggs e.g. to create new hybrid embryos or embryo-like beings, which would disrespect the human procreative faculties and their profound significance.

Legitimate concerns

"It is early to judge, but this research may perhaps prove helpful in avoiding the problem of a shortage of appropriate human organ donors as well as ethical problems with some organ harvesting concerning consent and determination of death. As with all such developments there are legitimate questions over safety, and a moratorium has been imposed by the NIH on such experiments due to concerns that human cells might migrate to the pig's brain with all that that implies. Brain cells, and also cells linked to procreative function, should be treated differently from other cells due to worries concerning the role the brain plays in personal identity, and the special nature of human gametes and their meaning in human life. 

"As always in such matters, a clear view as to what is being done and intended by the scientist allows us to assess these developments, which appear to be positive in principle, though perhaps not in practice. Only with such clarity can we then direct our attention to possible downsides in terms of any risks there may be to human health or animal welfare."

Alternative source of organs

Another bioethicist who has reflected on the ethical questions raised by this research is Dr Agneta Sutton, who pointed out last weekend in her regular Science column in the Catholic Times that:

[There] is an alternative source of organs, one that most people might well prefer. This is laboratory production of human organs using cells from the intended recipients. If scientists could go down that route, they would overcome the problem of rejection. And there would be no need for any kind of organ donation!

So I think that the lesson from the BBC's reporting can be summed up in the perennial advice when considering ethical questions: "Always distinguish" (Thomas Aquinas).