Human Genetics and Disease

The main benefit of genetic testing is early detection - it is vital for combating illnesses. Once a disease has been diagnosed appropriate treatments can be planned to make the patient better or manage the symptoms as best as possible (in situations where there aren't currently any cures). As our understanding of the genetic basis of disease and mutations experiences exponential growth more genetic tests are being designed and coming to the market place. The development of a genetic test can sometimes be the first fruits of research into an illness. For example, when scientists try and understand why some people are more susceptible to a rare genetic disorder such as Kawasaki disease they look for genetic variants that might explain this. When they find a set of unique genetic variants these can become the basis of future genetic tests.

If you ever have a genetic test there are at least five important questions you must ask about the procedure.

We are surrounded by pathogens and millions are crawling all over your body as you are reading this. Fortunately, most of them do us no harm whatsoever, and some are even beneficial. However, there are some that we want to avoid. Salmonella is a pretty nasty bacterium that causes food poisoning. Understanding how it functions at the molecular level will lead to strategies that will halt its destructive behaviour. The more we know about how our tiny enemies operate, the better our chances of winning the battles against them as new and improved drugs and medicines are designed.

Another way of finding out more about disease causing pathogens is to study their genomes and construct genome maps. Genome maps of two parasites that cause Malaria are leading the fight against one of the world's biggest killers.

The technology that has yet to bear any real fruit is the genetic engineering of humans, and principally by that I mean gene therapy. That's where you swap the bad genes in your body that are causing disease with good ones. The beneficial genetic material can be carried on a virus that's had its virulence factors neutralised and then sent into your body. However, though there have been some successes, the fact that it is not yet a common procedure is due to the enormous technical challenges that are involved in getting a desired gene to a specific location in a patient's body.

This field of scientific research is also highly contentious and the pros and cons of human genetic engineering are debated at length. There are risks involved (as there are with all medical advances) and some people worry about nightmare scenarios of a future where parents construct or chose their children from a pool of perfect genes.

Many of these fears are of course wide of the mark and fuelled by the tabloid press, though that is not to say that some are without merit. There are very genuine concerns about genetic technologies, and they are not risk free. But they can only really be debated by a properly informed society. It would be unwise to throw a technology out of the window based on uninformed fear and speculation.