By birth, nine weeks, a female baby has only 2 million eggs contained in her uterus.
Despite these relatively large numbers, females only use 360 eggs in a lifetime, although as mentioned above, the eggs a female releases later in her life are much less fertile.
- One way of combating this infertility in older women is to insert mitochondria from a donor egg into a recipitant egg, which means the cell has/can produce much more energy to divide and therefore develop into a foetus. However, there seems to be a very serious implication of using this method to manipulate reproduction as well as the ethical issues involved, many of the children born using this technique have chromosome mutations, which are potentially lethal.
This manipulated/aided reproduction has the potential to produce a child with up to 5 parents:
- Donor sperm
- Donor egg
- Donor Cytoplasm
- Donor mitochondria
- Surrogate Mother
Using embryonic cells to test for genetic disease/mutations:
It is possible to safely remove a single cell from an embryo without destroying the other cells that make up the embryo. In doing so this creates a number of possibilities for testing the embryo against genetic diseases and mutations. Using this method it is possible to predict whether or not the embryo will survive long enough to come to full term and therefore be born. Moreover it is also possible to see if the embryo has inherited any genetic disorders or even developed any genetic mutations as a result of DNA copying errors. This can either prepare the parents or have more adverse effects for example termination of the pregnancy. For this reason Ethics must be involved when using this test.
Under the umbrella of cell mutation is the repeated copies of some chromosomes, for example three copies of chromosome 18, which is linked to miscarriage. This means that although embryos with mutated chromosomes are born, in lots of cases those embryos that have many mutated chromosomes, the embryo simply dies, there are too many mutations for the embryo to develop into a baby.
Thus apoptosis occurs – cell death. The embryo dies and a miscarriage occurs. However if the environment intervenes and allows the abnormal cells to develop and be born, the chromosome mutations can be such that the baby is diseased or disfigured.
The female body produces FSH (follicle stimulating hormone) naturally, however research has found that when a pregnant female is injected with a large dose of FSH, the embryo changes, i.e. the chromosomes within the embryo become mutated.
Quantification of TSC2 mRNA transcripts after embryo freezing:
When a female develops cancer and chooses to undergo a course of chemotherapy, the radiation can permanently mutate her eggs, thus making her infertile or at least unable to give birth to a child that has not got a genetic mutation/disease. To overcome this problem many females have, there have been suggestions to use a technique called ‘embryo freezing’. At first glance this technique is wonderful in that it means cancer patients do not have to become infertile. However, close examination has proved that embryo-freezing leads to changes in gene expression, in other words the genes are mutated and may therefore cause a greater susceptibility to cancer.
Problems involved with cloning:
- Embryo Loss
- Abortion
- Foetal Death
- Obesity
The use of stem cells and transgenics
Stem cells can be used to treat many diseases, illness’ and injuries, as does the use of transgenics, which mean that a cell, or gene is inserted from an animals body into a human body creating the desired production of chemicals that will lead to the cure of the said disease/illness/injury. One such example is the contributing cure to Parkinson’s disease by replacing the dopamine producing cells in the brain.
- Stem cells have the potential to deal with defence against diseases.
- Transgenics can help us to understand the action of a single gene
- Transgenics can focus on gene interaction e.g. knock-out
- Finally, transgenics can help us to make animal models of human diseases
However, an interesting point to make at this stage is the fact that genetic mutations can have positive effects. For example the HIV virus can be used to modify DNA in the nucleus and while this has adverse effects i.e. AIDS, by manipulating this virus we can modify DNA within the nucleus to cure other genetic mutations.
Furthermore, there is a genetic disease that exists which despite its adverse effects; it has survived for more than 3000 years because it also protects the sufferer from malaria. Therefore it is safe to say that although some genetic modifications are bad, some of these genetic modifications have been allowed to evolve freely because of their ‘greater good’.
Professor Lord Winston’s ethical justifications for abortion:
An embryo is simply a bundle of cells, however a foetus is viable. Given that only 18% of embryos develop and come to full term as a baby, there is a very important distinction between the two, and aborting an embryo should not be considered murdering a baby, as the chances of it even becoming a baby are very low.
The time it takes for an embryo to become a foetus is 8 weeks, as explained below and so past this period there should be more consideration as the chances of the foetus coming to full term are higher.
14 days 4 weeks 8 weeks
Nervous System Heart Started All Organs
Developing Beating Developing
Final thought: Genetic modifications should protect, not risk.
