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PGD: The Search For Genetic Diseases

Extracts from this document...

Introduction

Contents .................................................................................................................. 2 What is Pre-Implantation Genetic Diagnosis? ......... 3 The Procedure .......................................................................................... 3 What is PGD used for? ........................................................................... 4 Diseases which PGD can test for ............................................. 4 Could PGD be used to choose the sex of a baby? ... 5 Advantages & Disadvantages of PGD ................................. 6 The Reliability of PGD ........................................................................ 6 Ethical Issues .................................................................................................... 7 Personal Viewpoint .................................................................................... 9 Evidence .................................................................................................................. 10 Reference List ................................................................................................... 11 Pre-Implantation Genetic Diagnosis (PGD) is a type of genetic testing. It is defined as: "a technique used during in-vitro fertilisation (IVF) to test embryos for genetic disorders prior to their transfer to the uterus." (http://www.bcmivf/Glossary.htm) Firstly the women is given drugs to produce 'super-ovulation'. Using standard IVF techniques, the eggs are placed in a dish and fertilised with sperm. After about 3 days, the embryo has divided into about 8 cells. The photo shows the start of the procedure. The embryo is fixed in position with a holding pipette (shown on the left). A second pipette (on the right) is used to drill a hole through the shell of the embryo and a single cell is removed. This cell is then "subjected to a molecular analysis. ...read more.

Middle

This may not be the case, and on occasion, PGD may result in a false negative result, leading to the acceptance of an abnormal embryo, or in a false positive result, leading to the deselection of a normal embryo. (http://en.wikipedia.org/wiki/Preimplantation_genetic_diagnosis#Ethical_issues) When tests are carried out, there can be difficult decisions to make once the results have arrived. Here are some decisions and viewpoints: 1) Some people prefer not to know if their baby has or has not got a genetic disorder: they are against PGD. However, is this fair on their partner or any future children they might have? 2) Is it right for someone who is at risk of passing on a genetic condition to have children? However, is it fair to put them under pressure not to, if they decide they want children? 3) If a test result is positive, is it right to terminate the pregnancy? Some people think abortion is wrong, whatever the circumstances. 4) Is it fair on the parents to have a sick or disabled child, especially if they wouldn't be able to cope? But does that child have less right to life than a healthy child? ...read more.

Conclusion

Look at the graph below. As you can see, with pregnancies after PGD has been used: * The miscarriage rate has been reduced considerably; * The implantation rate of embryos has increased drastically; * The 'take home baby' rate has increased radically. All of these changes are beneficial, so PGD has proven itself to be quite effective (despite the 2% rate of being unsuccessful). (Graph taken from Reproductive Genetics Institute: www.reproductivegenetics.com/aneuploidy.html) Definition of PGD : (http://www.bcmivf/Glossary.htm) The procedure of PGD : (http://www.religioustolerance.org/abo_pgd.htm) Quote on PGD procedure : Luba Djurdninocic, "Pre-Implantation Testing," (http://www.vhl.org/) CGP (Coordination Group Publications). (2006) GCSE Core Science OCR 21st Century, 1st Edition, Newcastle upon Tyne: Elanders Hindson Ltd What is PGD used for? / Could PGD be used to choose the sex of a baby? : (http:// www.bbc.co.uk/sn/tvradio/programmes/horizon/babies_qa.shtml) Diseases which PGD could test for : (http://www.religioustolerance.org/abo_pgd.htm) Advantages/Disadvantages of PGD : (http://www.genetics.com.au/images/afactsheets/fs16_1.gif) Reliability of PGD : (http://www.cpmc.org/services/pregnancy/information/pgdbrochure.html#What%20Is%20The%20Reliability%20of%20PGD?) Ethical issues : (http://en.wikipedia.org/wiki/Preimplantation_genetic_diagnosis#Ethical_issues) Jeffrey R. Botkin. (1998) Ethical Issues and Practical Problems in Preimplantation Genetic Diagnosis, 1st Edition, Volume 26 Jason Christopher Roberts. (2002) Customizing Conception: A Survey of Preimplantation Genetic Diagnosis and the Resulting Social, Ethical, and Legal Dilemmas, 12th Revision, Duke L. & Tech. Evidence (Outcome of Pregnancies Before & After PGD) : (http://www.reproductivegenetics.com/aneuploidy.html) Graph was slightly modified for use in this project. ?? ?? ?? ?? Page 1 of 11 ...read more.

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