This is a page from genefaith.org created by Andrew J. Palmer
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Discussion on Ethics of techniques in Cloning and IVF
The study of DNA and the understanding of genes
has brought a vast range of new opportunities to help people,
but also to bring harm, and to change things for changes sake.
The pages in this applications section are designed to give some insight into these areas
and to give access to further information both in books and through the web to areas that
interest you.
Knowledge is not free.
It places upon those who know a burden of choice. Knowledge can be used or abused.
It can bring freedom life and happiness for many, but it can also bring misery, suffering
and instant or painful death.
1. Overview
The chart in the IVF or Assisted Conception core page shows the different paths to produce a zygote.
Zygotes for all these processes, if intended for implantation would be grown to about the eight cell stage. Then tested for genetic abnormality. Satisfactory eggs could then be implanted.
Ooplasm transfer (Dr. Jacques Cohen, New Jersey) - adds mitochondria from the donor cell although it adds no nuclear DNA.
The testing process requires
a. visual examination - a considerable number of genetic abnormalities can be discerned
visibly
b. removal of one cell from the blastula or morulla
c. if a specific family history indicates the presence of a family history towards certain
problems then those problems can be looked for.
e.g. Turner's syndrome - missing X chromosome - (all other missing chromosome
abnormalities either abort naturally or fail to implant). Most Common from an extra
chromosome is Down's Syndrome (extra chromosome 21), other possible are e.g. Klinefelter's
(extra X), Patu's (extra 13) and Edwards (extra 18).
2. Development of Embryos
There is a lot of controversy surround the use of embryo's for experimental research.
So first some information about the development of an embryo and then some ideas and arguments. (see human development chart )
Nobody experiments on embryo's, the law only allows work to be done on morulla and blastocysts.
General definition is that the amount of development that defines and embryo hasn't occurred until after 14 days.
Development is the key issue here.
The zygote, (the single cell formed from the fusion of sperm and ovum),
begins dividing after about 30 hours.
For the next 5 days every cell in the forming morulla is absolutely identical.
As growth by division proceeds the morulla or blastula, becomes a hollow sphere of cells
called a blastocyst. The outer cells of the ball will become the placenta and the inner
cells will develop into the embryo and thence into the baby.
By day 7-9 if this is taking place inside a female, the cell ball will implant and begin
to develop further.
Round about day 14 or shortly following the first signs of cell differentiation take
place. A dark streak can be seen across the centre of the ball of cells. This streak will
become the spinal chord. At this point the cell mass is called an embryo and further
differentiation takes place until by eight weeks every kind of tissue is present, and the
beginnings of every organ that will be present in the fully formed adult.
So up to 14 days all the cells in the mass are identical. They are known as Stem Cells, because all other cell types stem from them.
splitting of the morulla or blastocyst produces identical twins / quads etc.
In fact if you wanted an army of identical people this would be the point to act. Keep splitting the morulla and every cell has the ability to produce a complete adult.
Sometimes the embryo attempts to split (i.e. shortly after the 14 day
stage, and after differentiation has started)
At this stage not every cell can produce an whole adult. The splitting is usually on
partial, and the result is Siamese twins.
3. Therapy from Stem Cells & genetic engineering.
There are several important arguments relating to the use of stem cells (cells from the morulla or blastocyst) for research and therapy. (Therapeutic Cloning)
every cell at this stage has the potential to become a whole adult.
But potential is not actual. A great many things have to happen before a potential
something becomes and actual something.
e.g. some parts of the seabed are potentially mountains. The geological environment means
that with the right upheaval they could be pushed up to become mountain tops. It's not
necessarily desirable, nor essential, nor inevitable but that doesn't deny the potential.
So some level of respect is due because of it's potential - but no the rights and
privileges of the adult, or even the embryo.
Since we do not have artificial wombs capable of producing full term growth of embryos, only cells implanted in a womb will ever become babies and realise their potential to be adult. Until then they are only cells. (Eggbert the mouse - grown principally in a lab - Jackson Laboratory, Maine, team led by John Eppig. At birth appeared normal, fathered a few pups, at six months became obese, developed neurological problems and died. The egg "is not just a quiescent little blob" says Kate Hardy a reproductive biologist at Imperial College London, "there's an incredible amount going on..." (from Stop the Clock, Claire Ainsworth, Jun 2001, New Scientist))
Then we need to think about how the body treats eggs and zygotes.
A young female starts of with 7 million of eggs in her ovaries.
When born that has diminished to about 2 million.
By the time she is old enough to children that has dwindled even further..
Of say the million remaining some 400 - 500 will develop from the ovary and be emitted for
potential fertilisation. Of those a handful may be fertilised. Of those about 55% will be
aborted before the embryo is 12 weeks old.
In the Western world, usually less than half a dozen will be born as babies - the average
is about 2.
With any other outcome - either the human race will fill the planet in less than a
generation, or die out completely.
So if on a racial scale enough babies are being produced - why all the fuss about a few
extra cells that would be waste as far as the body is concerned.
If a woman's body can throw that many away - why can't she choose to allow a few of them to
be used for other good purposes?
The source of stem cells is waste zygotes/morulla/blastula from IVF treatment, i.e. when
the woman has had the babies she wants out of IVF the rest of the eggs are waste.
4. Failure of Zygotes produced by unusual means.
Cloning is not an exact science. It is about the manipulation of of
cells on a gross scale.
A micropippette is inserted into the egg cell. The nucleus is removed and replaced with
the nucleus from another cell from an adult cell.
Then with an electric jolt the cell is tricked into thinking that it is a fertilised egg
and it sets off growing.
Dolly: was created from the single success in 277 attempts to produce a viable zygote.
Copy Kitten: is the only resulting kitten from 87 embryos originally created.
5. Biblical Perspective
How does the practice measure up to biblical themes.
What are the major biblical ethical themes and how do they apply here?
The themes are I see are:
Which of these would it be right to draw into an examination of this issue. First responsibility, second exploitation, third respect.
discClone.htm