Gene mapping has made it possible to see where the HIV virus hits [GETTY]

Joe was upset. He always knew that things could get tougher as he entered the thirteenth decade of his prolific life. "The teenage of the new age" as a friend called it, had not been exactly exciting. He was told that he had developed a malignant brain tumor. To make matters worse, the doctor told him that he could not postpone treatment. He sounded serious.

Joe stepped into a pharmacy and handed the prescription to the clerk. The clerk disappeared behind rows of medicine shelves and came back with a tiny box, containing a nasal drop especially designed for his condition.

"Well, two days of rest and things will go back to normal," Joe thought as he played with the box. "Things might have been seriously complicated a hundred years ago."

Joe's situation may sound like a scene from a sci-fi movie, but when the completion of human genome mapping was announced 10 years ago, many thought that such scenes would soon become part of everyday life. The greatest achievement in cellular biology and genetics certainly heralded longer, much healthier lives for the human race, as well as easier treatment for some incurable diseases.

Expectations exceeding reality

Regardless of the results, the fact that scientists had decoded the human genome was quite astonishing. Genes are combinations of four protein molecules sitting alongside each other in countless possible orders on strings of helical structures known as DNA. DNA strings are wrapped in protein sheets forming chromosomes.

Chromosomes are coiled in cells' nuclei, keeping data about how to survive, what to make, when to reproduce, and eventually, when to die. Gene mapping has helped scientists develop an understanding of where each bit of such information is stored on each chromosome. Furthermore, they know what every gene is capable of in regards to the well being of the human body.

The human mind tends to ignore the agonising efforts that made this possible and expectations immediately exceed reality. The real impact of gene mapping in clinical care is yet to be seen in mainstream health care.

It is true that human genome mapping entails many promises, from longer life expectancy to improved sports records, but a lot of hard work and time is needed before any of these promises materialise.

Human testing

Aids is a good example. When the first cases of the Acquired Immune Deficiency Syndrome were reported and the HIV virus was discovered in the 1980s, it quickly turned into a collective nightmare. The HIV virus changes the cellular DNA, switching off the cell's defences. Once the message becomes part of the cell's DNA, its mind, it keeps reproducing it.

Gene mapping has made it possible to see where the virus hits. It is now possible to target the specific sequence of the DNA that is sending the wrong message, block it, and help the cell resume its normal activity. It sounds like the perfect solution to a difficult problem, but it would not have been possible without the human genome map.

It is also possible, in laboratory experiments, to disrupt a DNA string, plant a sequence in a specific location and sew it back. This means that a defective gene can be replaced with a brand new one. This opens the way for correcting the cell's mind and behaviour and it has been used In-Vitro (in the lab) to cure cancer.

The main problem is that such experiments have to be tested on human beings before they are considered successful treatments. And human life is too precious to be subject to such tests. Besides, genetic diseases are rare and that means the chances of carrying out such experiments In-Vivo (on live cases) are extremely slim.

Shining a light

While genome mapping presents many exciting possibilities, there are also other potential consequences that should be kept in mind.

The genetic consultation is now a routine part of counseling before having a child. In the light of new technology and genome mapping, a couple can be told that their child may suffer from a specific condition that neither of them have had but the cause of which they have carried as recessive genes in their cells. With new techniques available, that gene could be blocked before the child is born.

But this could have serious consequences. Once people are given the chance to change their children in a way they deem appropriate, what would stop them from changing an unborn baby into a super child? More broadly, what would stop the creation of a new breed of human with super powers and enhanced intelligence?

What would stop governments, the rich and powerful from creating their own armies of cloned men and women who could change human history once and for all? And what would be the outcome of such ambitious, if not evil, plans? The prospects do not seem to be entirely rosy after all.

The secrets that once lay in the nucleus of every human cell are now out in the open. Yet another Pandora's Box has been opened by intrepid scientists. And as they move slowly but surely forward in their endeavors, while perhaps failing to match the imaginations of science fiction writers, they will certainly present more options and possibilities to the next generation.

Light has been shone on another dark corner of human biology, and while there is always the chance that a great scientific achievement will be misused, no one can doubt that moving ahead with a map is preferable to not moving at all, in fear of getting lost.

Alireza Ronaghi is Al Jazeera's Iran correspondent and a qualified medical doctor.

Source: Al Jazeera