The newspapers talk about a breakthrough in DNA mapping. What does that mean?

The genes that ‘tell’ our body’s cells what to do and pass those instructions to the next generation are made of a chemical called DNA. This is made of four different types of chemical building block joined end to end and form the genetic alphabet (just as this article uses 26 ‘building blocks’ from our spoken and written alphabet). In the late 1980s it was decided to establish the human genome project (HGP). (Note the word ‘genome’ means the sum of the genes of a particular species). The Project has given us a first draft of the sequence of probably most of the 80 - 85,000 genes in the human body: ‘a first draft’ because there is extensive checking to be done, ‘probably most of the genes’ because there may be more to be found lurking amongst the non-informational DNA.

How significant is this?

For perhaps 50% of the genes, we do not know the function; we can read the letters but what instruction they give to a cell is not known. Further, we do not know how the living organism, in this case a human, orders the use of all these genes in order to drive the development from the single-celled egg to the fully formed person with their 70-75 million million cells. It is as if we had all the sentences of a book lying in a big heap and we had make the story out of them. Nevertheless, this is a significant milestone in our understanding of human genetics and we should recognise it as such.

Why is the HGP so important?

About 4,500 diseases are caused by malfunctioning genes that may well be passed to offspring Understanding exactly how these genes go wrong is already changing the way in which the symptoms of some of these diseases are treated and may lead to actual cures. Further, we are learning about how genes malfunction in a non-heritable way. Some cancers fall into this category. Finally we will continue to find out how genes work during human development. Some scientists suggest this research will enable us to discover why some people have a predisposition to certain behaviour patterns.

How would you respond? Some scientists would reduce humans to ‘nothing but our genes’. I, and many others refute that entirely. Nevertheless, we must recognise that a lot of our behaviour is influenced by biochemistry. Think how the simple chemical alcohol alters behaviour, or how the anabolic steroids taken illegally by some athletes can make them more aggressive. However, behaviour is clearly influenced by experience, by family structure, by social environment and so on. It can be changed through choice, through therapy and supremely by the transforming work of the Holy Spirit. There is nothing in human genetics that diminishes human responsibility.

What are the worrying aspects?

  1. The ability to test for over 200 gene malfunctions (the number is growing monthly) and to apply those tests to foetuses in the womb is certainly leading to increased numbers of abortions. In time, wealthy prospective parents may aim for perfection by asking for tests for fairly trivial conditions, or genetically manipulating a ‘test-tube’ embryo to impart a particular feature considered desirable.
  2. Will the possession of a gene that causes late onset of a serious illness or which gives a pre-disposition to serious illness disqualify someone from a job or from obtaining insurance? In fact, refusal of life or health insurance on genetic grounds has already happened in the USA.
  3. Let us not use genetics to excuse ourselves from looking after people (extreme right-wing politicians in the USA have already come up with the ‘born to be unemployed/homeless etc’ argument).

Scientists are often portrayed as immoral and only interested in research. How should we pray for them?

Some have high ethical personal standards, others do not; some are concerned only with themselves, others care for other people. However, one thing that unites us is that we are curious about the universe in which we find ourselves. Please pray especially for Dr Francis Collins. He is the Director of the Human Genome Project, based at the National Institutes of Health in the USA, and is also a practising Christian. He wants to see the results of the HGP used wisely under God for the relief of suffering and for the general benefit of humankind.