There are many websites that contain useful background information on the topic of genetic modification and the current debate

• A good place to start is the Bioethics Briefing on Pre-Implantation Genetic Diagnosis which contains background information on the scientific techniques and the ethical considerations 
• The Nuffield Council on Bioethics are an independent body who examine and report on the ethical issues within biology and medicine. A past project on genetic screening published a report in 1993 titled ‘Genetic screening ethical issues.’ 
• The Human Fertilisation and Embryology Authority (HFEA) have a question and answer page dedicated to PGD 

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