Science and Technology Committee

The creation of animal/human hybrids through this technology is a valid research tool from which we could learn a great deal. The act should be amended to allow the procedure, but strictly under a research basis only. There are enormous scientific hurdles (followed by public debate etc) to overcome before addressing such specific health issues as that exemplified.

This seems to me to be unethical at a number of levels. However nobel the proposed use nothing would justify the enormous moral implications of such a procedure. The legal status of the human embryo would in time be eroded by such procedures. The key issue for me here is the formation of an embryo with the potential of human life - a stem cell culture would not in my view be so terrifying.

Contributors to this discussion may be aware of research that is taking place in China (see this link http://www.mindfully.org/GE/2003/Human-Rabbit-Clone-Embryo14aug03.htm).

Is there an argument that such an embryo would not be human and could not produce a viable offspring makes it more ethical and not less? Researchers have created mice with some human genes so they can mimic some features of human physiology. This has been done because doing the same research on humans would be more unacceptable to many.

Should we not view hybrid embryos to create stem cell lines in the same way?

I believe the only justifiable reason for creating any embryo is to bring it to full term, and cherish it.

I am concerned that we seem to be increasingly living in a culture that views life as dispensable, unless of course it’s your own life. If therapeutic cloning is taken as creating a life merely to create spare parts for another life, then it has more in common with sustaining oneself by cannibalistic murder than it does with any notion of therapy in the Hipprocratic sense. As regards the creation of inter-specific chimeric embryos, we need to ask ourselves whether or not a human nucleus in the cytoplasm of another organism would actually be human or not.

At present, most people hold human life in some form of special esteem and view it as being of greater sanctity than that of the other species that we exploit for food and experimentation. It might ap pear reasonable that any developing living entity in which "the vast majority of the DNA is human" should be afforded the vast majority of human rights. However, I suspect that most of our distinct identity as humans owes as much to developmental contro l of gene expression as it does to the mere possession of distinctive coding sequences. Of course, I await completion of the chimpanzee genome sequencing project and subsequent comparative transcriptomics to fully address how regulation of gene expressio n influences the extent to which we visibly differ from other apes. In the meantime, I have doubts regarding the full extent to which human genes will result in human phenotypes if they are epigenetically reprogrammed by the oocyte of another species.

I n deed, we still know relatively little about how the maternal contribution of cytoplasmic RNAs and proteins or mitochondrial genes might influence the expression of genes from the transplanted chromosomes in hybrid embryos created by nuclear transfer. For all the discussion about human-cow, human-rabbit or other hybrid embryos, I know of precious little experimental work to address the developmental consequences of creating hybrids between distantly related mammals aside from humans. In the absence of an y direct evidence to the contrary, one can envisage various sources of potential incompatibility between human chromosomes and a non-human cytoplasm, with unforeseen developmental consequences. Surely such basic science should be performed first before e ven contemplating the applications of this technology to humans, if at all??

When is a human not a human? There are two conventional answers to this question. Consider the following alternatives:

A) According to various definitions of the biological species concept, individuals would cease to be humans if they could interbreed but are reproductively isolated from other humans.
To use a more precise definition similar to that of Ernst Mayr, an individual may cease to be a member of the human species if they are fertile on reaching sexual maturity but are unable to mate with other humans and thereby produce fertile offspring.

B) Individuals cease to be humans when their continued existence is an inconvenience to us.
We are aware of many cases where a denial of others’ full humanity is used to help justify their disposal, whether in terms of ethnic cleansing or destruction of life in its earliest stages.

I wonder, which definition of humanity will be applied to evaluate the humanity of life forms containing human chromosomes in a cell from another species…?