Fear of the clone word

Therapeutic cloning may be used as a cell therapy to reverse some of the most complex diseases known to mankind.

It describes the process of converting a cell of the body into a primitive stem cell, known as embryonic stem cells.

The method involves the fusion of a cell of the body - for example skin cell or cell from inside the mouth - with an empty egg cell.

The eggs are donated by women themselves or they may be a wife, partner, relative, friend or be anonymous.

The embryonic stem cells are primitive undifferentiated cells that grow as tiny colonies from the small nest of 15-30 cells within the ball of embryonic cells of the four-to-six-day-old structure called a blastocyst.

These are smaller than a full stop.

The nuclear genetic DNA is removed from the egg and the genes replaced from the nucleus of the body cell.

The fused product of egg and body cell is allowed to divide to around 100-200 cells, which are then grown in the laboratory to form the primitive embryonic stem cells that can be directed to form unlimited numbers of any cell of the body.

Why is this important?

The procedure, known scientifically as somatic cell nuclear transfer (SCNT), has been shown in animal studies to return the mature body cells used for fusion to a primitive stem-cell state.

A cancer cell, for example, will become pristine embryonic stem cells with no sign of the cancerous state.

In the case of cells from patients with motor neurone disease, the cells will show no evidence of the degeneration characteristic of the MND nerves.

Consequently, we can begin to understand the cause of some of the most baffling and complex diseases that include diabetes, Parkinson's disease, Alzheimer's disease, MND, numerous cancers, muscular wastage disease, etc.

Many of these conditions are not obvious until patients have the fully recognisable disease.

Study of these disease-specific embryonic stem cells may reveal the early and more subtle expression of the disease; consequently, earlier tests for diagnosis may be developed and new therapeutic options devised.

Scientists in many research institutions also want to study these disease-specific stem cells to try to develop new cell and drug therapies to prevent or retard diseases.

Screening the disease-specific embryonic stem cells with "libraries" of small molecules known to be involved in cell function may identify compounds that prevent the disease occurring in the laboratory.

These may then become new candidate drugs for evaluation in patient clinical trials by the pharmaceutical industry.

Scientists are learning how to direct embryonic stem cells into a wide range of tissue types, including nerves, blood, heart muscle, pancreatic islet cells and lung tissue.

These cells could be used to repair damaged or degenerating organs.

The embryonic stem cells may need to be compatible for transplantation in these new stem cell therapies that are being devised and under pre-clinical trials.

The use of the patient's own cells to derive embryonic stem cells for regenerative medicine would make them completely transplant-compatible, recognised by the body as self and not rejected.

The formation of embryos in the laboratory for treatment of infertility by mixing sperm and eggs is widely accepted by the majority of the community.

They are also in favour of embryo-freezing and the use of embryos for "IVF research", including new embryonic stem cells.

These fertilised embryos generally have the capacity to develop to term.

Nuclear-transfer embryos have little or no capacity to develop to term (fewer than

one per cent are able to and most are abnormal) but are able to form embryonic stem cells.

The reasons for this difference are complex and not well understood.

If we are agreeable to use "normal" IVF embryos for research, why are there more concerns for using nuclear-transfer embryos?

Strongly stated opposition to nuclear transfer to form disease and patient-specific stem cells must then arise from those who also oppose IVF, to be logical.

This is a minority of the community.

The opposition to forming embryos for research is not really relevant because there is no combination of sperm and egg involved.

Since nuclear-transfer embryos cannot ever be placed in the body of a woman, they are not formed with reproductive intention - they are formed to understand and possibly treat severe disease and injury.

Hence both by nature and intent they are not embryos in the usual understanding of this term.

Scientists are unanimous in their opposition to reproductive cloning and support strict regulation and community involvement in the monitoring of research on human embryonic stem cells.

Nuclear-transfer methods offer new research opportunities for conditions with few or no treatment options.

A loss of research momentum could be regrettable for those patients who may benefit from new therapies that will be devised using embryonic stem cells.

Given the moral opposition and concerns that exist in the community to embryo research, scientists themselves are determined to prevent unethical behaviour and will condemn those who are dishonest and deceiving.

The identification of problems in Korea by scientists is an example of their concerns and vigilance.

The Lockhart Review has highlighted the need to maintain high ethical standards in this area and ongoing monitoring of progress.

This review has sampled widely from community opinion and the recommendations are to be welcomed strongly by the Australian medical research community.

Opposition to embryonic stem cells on the basis that adult stem cells can cure all disease and injury is not supported by present scientific research.

It is the very strong view of world stem-cell researchers that we need to deliver outcomes for the broad range of disease applications needed.