Genetic Engineering
Disease Elimination
Disease, by its very nature,
has a genetic component. A disease is either
inherited or the result of the body's response
to environmental elements such as a virus.
At present human genetic engineering is primarily
carried out through a process known as Preimplantation
Genetic Diagnosis or Selection either PGD or
PGS. No real engineering takes place, what happens
is single cells are removed from embryos
using the same process as used in In Vitro Fertilisation
(IVF). These cells are then examined to identify
which are carrying the genetic disorder, which
are not. The embryos that have the genetic disorder
are discarded, those that don't are returned
to the uterus in the hope that a baby will be
born, without the genetic disorder. Only previously
identified genetic disorders can be tested for,
there is no 'catch all' testing.
What this means is that if the parents fear
their unborn child might inherit a disease or
disorder they can choose to have their embryos
tested for that specific disease or disorder.
Some examples of disorders that can be tested
for are:
Downs Syndrome
Tay-Sach Disease
Sickle Cell Anaemia
Cystic Fibrosis
Huntington's disease
There are of course many
others than can be tested for and medical
and scientific institutes are constantly searching
for and developing new tests.
This procedure is fairly uncontroversial, it
does however have it's
critics
who argue that human life starts at conception
and therefore the embryo is sacrosanct and should
not be tampered with or that we simply should
not be messing around with our genetic make
up and the results are unstable and unpredictable.
Another use for this technique is gender selection,
which is where the issue becomes slightly more
controversial.
Some disorders or diseases are gender specific,
so instead of testing for the disease or disorder
the gender of the embryo is tested for and whichever
gender is 'undesirable' is discarded. This brings
up huge issues about the ethics of gender selection
and the consequences for the gender balance
of humankind.
A more recent development is the testing of
the embryos for tissue matching. The embryos
are tested for a tissue match for a sibling
that has already developed or is in danger of
developing, a genetic disease or disorder. The
purpose is to produce a baby who can be a tissue
donor.
This is known as Sibling Savers.
Again this technique has caused much controversy
as the purpose of the testing was seen as being
not for the purpose of disease elimination directly.
This technique is one step forward in the search
for ways to treat and cure, rather than eliminate,
genetic disease and disorder and for finding
ways to use these techniques in the use of genes
as curers i.e the introduction of a modified
gene that could perhaps suppress a tumourous
growth. This is known as Gene Therapy.
The next step in disease elimination is to attempt
to refine a process know as Human Germline Engineering.
Whereas PGD affects only the immediate offspring
germline engineering seeks to affect the genes
that are carried in the ova and sperm and thus
eliminate the disease or disorder from all future
generations making it no longer inheritable.
The possibilities for germline engineering and
gene therapy go beyond the elimination of disease
and move us into the other spheres of influence
we identified earlier; longevity, capacity,
adaptability and fashion.
^ Top ^
