|
SRT Home Page What is the SRT Project? Site Map & Subject Index What's New? Highlights Current Talking Point SRT Publications SRT Newsletter SRT Information Sheets SRT Topical Papers Press Room Contact SRT Send a comment Guest Book SRT Trust & Associates Links European Christian Environmental Network Eco-Congregation |
|
Genetic engineering is an umbrella term which can cover a wide range of ways of changing the genetic material - the DNA code - in a living organism. This code contains all the information, stored in a long chain chemical molecule, which determines the nature of the organism - whether it is an amoeba, a pine tree, a robin, an octopus, a cow or a human being - and which characterises the particular individual. Apart from identical twins, your detailed genetic make-up is unique to you. Individual genes are particular sections of this chain, spaced out along it, which determine the characteristics and functions of our body. Defects of individual genes can cause a malfunction in the metabolism of the body, and are the roots of many "genetic" diseases.
Genetic mapping
Our understanding of our genetic makeup is being greatly expanded by a systemmatic mapping process known as the Human Genome Project, carried out internationally with enormous commercial and government funding. Smaller projects are also drawing the genetic map of pigs, chickens and some other organisms. As this work proceeds, individual genes are being identified for various functions and especially for medical conditions. Sometimes it appears that a single gene is responsible, for example in cystic fibrosis, but most conditions seem to be caused by more complex sets of factors, both genetic and environmental. We should make an important distinction between a gene which causes a condition outright, and one that gives one a susceptibilty to it, but which requires other factors to be present as well for the condition to develop. The ability to detect such genes now means we can use the tests for screening, especially pre-natally. This raises some important ethical questions, as we shall see.
Screeing for various diseases is not, strictly speaking, the same thing as manipulating or "engineering" them. Some people feel "engineering" is an inappropriate term, with connotations of cold mechanics rather than living things, but it does reflect that manipulating genes has in some cases become a relatively common laboratory technique. We should also put it in context, that genetic engineering has been performed for centuries in animals and plants by selective breeding. This enhances particular genetic traits based on outward appearance, by choosing, for example, which boars to mate which sows to develop, over many generations, leaner pig meat.
Return to Contents
Genetic manipulation
From the early beginnings in the 1970's, however, it has now become possible to manipulate specific genes at a molecular level, using laboratory procedures on material taken from living organisms, which can be replaced in the organism, or put into a different one. It can be likened to taking a long, thin garment with a constantly varying pattern along its length, snipping out a section of pattern (an individual gene), modifying it and putting it back, or putting in a section with a different pattern (gene) taken from another garment. In principle, this ought to be much more specific than selective breeding, but the uptake of the relevant modified gene is often quite low, particularly in animals. It also allows the creation of "transgenic" organisms, where a short section of genetic material from an unrelated species can be introduced into another (N.B. a transgenic animal does not mean a 50-50 mixture!).
Return to Contents
Some Uses of Genetic Engineering
But why should we do this manipulation, be it within or across species? The purposes of doing genetic engineering are many and various. A range of them are listed below. These include :
There are of course many more specific questions. We have pages on a number of key issues :
Ethical Issues in Genetic Engineering in Animals and Plants
Genetically Modified Food SRT's pages on an area of huge current controversy, including our new report to the 1999 General Assembly
Xenotransplantation for one particular example of the potantial use of genetically modified pig's hearts in humans.
Patenting Life?
Return to Contents
This page has been produced by the Society Religion and Technology Project of the Church of Scotland. For more about our work on other issues, see our Other SRT Project pages, or our SRT Publications List.
We'd also welcome any comments you may have. We don't claim to have said the last word!
If you want to send us a comment or obtain further information or receive our latest Newsletter,
email us at :
mailto:srtp@srtp.org.uk
or send an ordinary letter or fax to :
Dr.Donald M.Bruce,Return to the top of the Page
Return to Contents
Return to Further Information
Go to SRT Contents Page
Return to SRT Home Page
