The mammal copiers – advances in cloning
Box 3 | On human cloning
In 1998 the Academy initiated a project on human cloning with the aim of contributing to informed public debate. In February 1999 the Academy's Council unanimously endorsed a position statement titled On Human Cloning.
Here is the executive summary of the statement
We define cloning as production of a cell or organism with the same nuclear genome as another cell or organism. We have chosen this simple definition to reduce ambiguity in public discussion, to guard against legislative misinterpretation and to underpin any regulatory or licensing guidelines. In this Statement we distinguish between reproductive cloning to produce a human fetus and therapeutic cloning to produce human stem cells, tissues and organs.
It had been widely accepted that cell differentiation (or increasing cell specialisation) in the developing mammal is irreversible, until the recent successful reproductive cloning of sheep, cattle and mice from adult cells. These experiments suggest that it may also be possible to reprogram human adult cells to revert to earlier stages of development. Speculation in the popular press about selfish or compassionate reproductive cloning of humans has tended to obscure the real scientific challenges in capturing this advance in knowledge for therapeutic cloning, for the benefit of mankind.
Cloning techniques may one day revolutionise medical treatment of damaged tissues and organs, should it become possible to use human adult cells as the starting material for growth of new tissues. At present, one human organ, skin, can be grown in the laboratory to provide self-compatible skin grafts for burns victims. The possibility of growing other self-compatible cells, such as nerve cells for patients with spinal injuries or muscle cells for heart attack victims, could one day be a reality, albeit within an unknown time-frame. That such a possibility could become a reality is suggested by the combined application of knowledge arising from three recent and significant advances in biomedical research.
These advances are (a) the cloning of mammals from adult cells; (b) the establishment of cultures of 'all-purpose' cells, human embryonic stem (ES) cells with the potential to grow into many different cell types; and (c) the demonstration that human fetal nerve stem cells can develop into multiple and appropriate nerve cell types following transplantation (into experimental animals). These findings provide new opportunities for research in cellular and developmental biology and, taken together, suggest that future possibilities may exist for self-compatible tissue and organ repair.
The Council, in accord with international opinion, considers that reproductive cloning to produce human fetuses is unethical and unsafe and should be prohibited. However, human cells, whether derived from cloning techniques or from ES cell lines, should not be precluded from use in approved research activities in cellular and developmental biology.
In Australia at present, production of human ES cells would be approved only in exceptional circumstances under National Health and Medical Research Council (NHMRC) Ethical guidelines, originally prepared to ensure ethical practices in in vitro fertilisation (IVF) clinics. For Australia to participate fully and capture benefits from recent progress in cloning research, it is necessary to revise the 1996 NHMRC Ethical Guidelines on Assisted Reproductive Technology and repeal restrictive legislation in some States. This could be done in the context of establishing a national regulatory arrangement, taking into account recent advances in biomedical research and advocated best practice elsewhere. The regulations should be binding on both publicly and privately-funded research activities.
Noting that the Australian Health Ethics Committee (AHEC) has recommended (December, 1998) that the Minister for Health and Aged Care should urge States and Territories to introduce legislation to limit research on human embryos according to the principles set out in the NHMRC Ethical Guidelines on assisted reproductive technology, the Council of the Australian Academy of Science makes the following recommendations with respect to existing and any proposed regulatory and legislative arrangements regarding human reproductive and therapeutic cloning.
Recommendations
- Council considers that reproductive cloning to produce human fetuses is unethical and unsafe and should be prohibited. However, human cells, whether derived from cloning techniques, from ES cell lines, or from primordial germ cells should not be precluded from use in approved research activities in cellular and developmental biology.
- Council strongly supports the recommendation of the Australian Health Ethics Committee that the Minister for Health and Aged Care should encourage and promote informed community discussion on the potential therapeutic benefits and possible risks of the development of cloning techniques.
- If Australia is to capitalise on its undoubted strength in medical research, it is important that research on human therapeutic cloning is not inhibited by withholding federal research funds or prevented by unduly restrictive legislation in some States.
- It is essential to maintain peer review and public scrutiny of all research involving human embryos and human ES cell lines undertaken in Australia. Council supports the view that a national regulatory two-tier approval process be adopted. Approval to undertake any research involving human embryos and human ES cell lines would need to be obtained from a duly-constituted institutional ethics committee (IEC) prior to assessment by a national panel of experts, established by the National Health and Medical Research Council, on the scientific merits, safety issues and ethical acceptability of the work.
Boxes
Box 1. Propagating plants
Box 2. How Dolly the sheep was cloned
Related sites
Whither cloning? (The Royal Society, UK)
Human cloning: Ethical issues (United Nations Educational, Scientific and Cultural Organisation)
Page updated November 2004.