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.