With new advances in genetics, there are some inherited disorders which can now be diagnosed at a molecular level. For couples who are carriers or affected by any of these conditions and are at high risk for transmitting it to their offspring, it is currently inherent to detect the disorder while pregnancy. This is done by one of two approaches: amniocentesis or chorionic villus sampling (which involves taking a small sample of the placenta at an early stage). However the couples have the dilemma of either or not to desist the fertilization if the genetic abnormality is present. In some cases this may also not be a viable choice for religious or moral reasons. An alternative would then be to diagnose the condition in embryos before the fertilization is established. Only the unaffected embryos would then be transferred to the uterus. This technique is referred to as preimplantation genetic diagnosis and would obviate the need for screening while a fertilization and hence preclude the physical and psychological trauma associated with inherent termination.
Abortion
Research towards developing techniques for early genetic diagnosis in humans were initiated in the Uk in the late 1980s (Handyside et al, 89, Lancet.347. And Dokras et al, 90, Hum Reprod, 5.821.). In vitro fertilization (Ivf) techniques are used to derive ova (eggs) from the mother which are then fertilized in the laboratory with sperm obtained from the father. One or more cells are then removed from the developing embryo 2 to 4 days after fertilization. This highly sophisticated technique called micromanipulation does not adversely sway added improvement of the embryo. The cells removed are then used for analysis, and the results can be obtained within 12-24 hours. The embryos without the genetic defects are then transferred into the uterine cavity to fabricate into a general pregnancy. Roughly all genetically inherited conditions that are diagnosed in the prenatal duration can also be detected in the preimplantation period. At the 8 cell stage, each cell of the embryo is still totipotent (each cell has the potential of forming an entire new organism). Thus, one cell can be removed for genetic testing without altering the improvement of the rest of the organism.Diseases which have a high risk of transmission (25-50%) and are commonly associated with needful morbidity and mortality can be screened for by this technique. The first report of the thriving application of this technique came from the Hammersmith Hospital, London, Uk which currently is the centre with the highest amount of births following preimplantation diagnosis
Now the Uk Human Fertilisation and Embryology Authority has given permission to Leeds parents, Shahana and Raj Hashmi, parents of a boy from Leeds who suffers from a potentially fatal genetic disorder that they can use Ivf to originate a sibling whose cells could cure him. This effectively means that doctors can use the procedure to ensure their next child can contribute their son Zain with a viable bone marrow transplant. The process requires doctors to artificially inseminate eggs from Hashmi's parents, then opt one embryo that matches his blood type that can yield the antigens needed to fight the disease. Embryos that did not match the strict type would most likely be destroyed.
Doctors say that the odds of success for this procedure are about one in two, but moral and ethical dilemmas surrounding the procedure have meant that the case involves some very involved issues. Effectively, the Hashmi family want to originate a child who would be a favorable donor for Zain, who suffers from thalassaemia - a rare blood disorder. This decision comes after the authority decided in principle in December to approve Pgd in cases of serious genetic disease, but that all applications by clinics to undertake rehabilitation should continue to be decided on a case-by-case basis only after rigorous examination of the ethical and healing implications of the rehabilitation and the welfare of the children. The case is similar to that of Adam Nash, an American boy conceived in order to contribute transplanted tissues to his sick sister. The procedure raises serious concerns about the potential to recognize the gene flaw and using a child as a commodity. The Human Fertilisation and Embryology Authority in the uk also recently give permission to Dr Taranissi at the Assisted fertilization and Gynaecology Centre in London by to use the technique.
When an embryo becomes a man with "human rights" is probably the most controversial debate of our time. It is an issue that has perplexed the wisest philosophers and the midpoint citizen. In Ireland. Although our moral attitudes are based on deeply held religious and ethical beliefs, it is becoming difficult to derive consensus on Roughly any issue although communal procedure must finally report an attempt to arrive at a inexpensive accommodation to differing interests. Despite the Irish peculiarities concerning the wording of the last amendment to our constitution, when human rights and protectability embark on should not become an all-or-nothing matter. Some people say prior to implantation that the embryo does not have human form or genetic uniqueness, as it is a growing collection of cells which can divide into two and simply yield selfsame twins, it is unable to survive surface of the womb, does not have any organ structures along with even a primitive brain and it has no degree cognitive development. They also say that after plan following intercourse some 60 percent of human embryos are discarded by nature at this stage of development, often even before the mother ever realises that she was pregnant. Hence it would be difficult for community to ascribe "rights" to something that has such a high natural mortality. Others feel that the creation, destruction or manipulation of human embryos by any method for any purpose, can never be justified.
Whatever your personal opinion, there is minuscule doubt that the technique should greatly growth the chances of predicting which embryos are likely to result in a thriving birth with much greater accuracy and effectively this technique is a big step transmit for Ivf as it means that doctors can now weed out question embryos before a woman becomes pregnant. The Uk legislation means that question embryos in certain circumstances can now be discarded, and only those with a good opening of success implanted into the woman's womb. However, this law is far from perfect, and up to 50% of embryos that look general under a microscope in fact include defects in their genetic material.
Personally, I believe that in Ireland we need a panel consisting of bioethicists, sociologists, physicians, basic scientists and professionals in communal procedure to re-examine the sensitive issues surrounding reproductive rehabilitation and embryo research, and then make recommendations about the areas of rehabilitation and science on which the Government should legislate. I also personally believe that the human embryo is costly and deserving of our profound respect because of its broad inherent and both its existence and status shold rest in the moral trust of the concentrate from whom it came.
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