Stem Cells

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Cell
A cell is the basic building block of the body; it contains a nucleus which is made up of chromosomes.
Chromosome
A chromosome is made up of strings of DNA which form genes.
Genes
Genes are the units of DNA which determine the characteristics of a creature.
Conception
Conception takes place when a sperm from a male combines with an ovum from a female to form an embryo. This process can be achieved through a laboratory process known as IVF (In Vitro Fertilisation, literally "In a glass"). In the course of effecting IVF more than one embryo is created and those not implanted to form a foetus are discarded.
Foetus
A foetus is created when the fertilised egg, the embryo,  is implanted in the womb, either by a natural process or medically after IFV.
Stem cells
Stem cells can be harvested from the discarded embryos which result from the IVF process. They can also be harvested from umbilical blood at birth and bone marrow in children or adults. These cells are able to be cultivated to form successor cells which in turn can produce parts of the body such as blood cells, heart tissue and brain cells. Embryonic stem cells are much more versatile than other stems cells.

Medical research

So far adult stem cells have only had limited use as in the treatment of leukaemia but, as time goes by, they will be used more effectively; conversely, developments may mean decreasing dependence on embryonic stem cells as other sources are used more effectively. In any case, 'lines' of cells can be developed from initial source material.

Ethical Questions

Some of the fundamental ethical questions which the above material raises are:

  • Is it ethical to use discarded embryos (the by-product of IFV procedures, for example) as a source of stem cells for medical research and intervention?
  • How different is this from taking the same stem cells from an embryo which results in its destruction?
  • Again, how different is this from taking stem cells from an aborted foetus to produce rubella vaccine?

Notice the change from "Embryo" to "Foetus" in this list; this is an issue we also need to think about. Behind these questions is the fundamental question of what constitutes a human being.

Cloning

The ethical questions about cloning - producing creatures from stem cells rather than an ovum - are related but separate as they involve creating creatures as opposed to providing existing creatures with better medical cures or with medical care.

Partly taken from HFEA.

PH/KC ix/05

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