DNA-analyses
Since the publication of the message below, the market for DNA analysis has developed explosively among professionals as well as in the DIY market. There are countless providers and the predictions are getting better and better.
In Estonia, all inhabitants can have their DNA tested for free. The result will then be discussed with the client by the general practitioner. A large group of residents have already had themselves tested or signed up for it.
Based on the experience there and the first experiences in the Netherlands, it appears that people are very satisfied with the service if the test is on a voluntary basis (3), although the question still arises whether people would like to have all this information. That is why general practitioners from the care sector are also reasonably satisfied (2). They can give good advice on early diagnosis and personal advice on diet, medication and life-style. A disadvantage they find is that the results do not always go through the general practitioner and there is nothing regulated by law.
For data scientists, the projects are the cream of the crop (3).
Human genome deciphered
Washington (USA) – What was once presented as the Apollo project of biology received its completion on Monday 26 June: the representation of all human genes. According to many biomedical scientists, the genetic revolution in medicine has begun.
Today, J. Graig Venter and Francis S. Collins announced simultaneously that they have deciphered the human genome. The race to be the first to crack the human genetic code comes to an immediate end. The titanic battle was fought between the American biotech company Celera Genomics, led by Craig Venter, and a group of laboratories, the Human Genome Project (HGP) consortium, led by Francis Collins. The HGP was mainly sponsored by the US National Institutes of Health and the British Wellcome Trust Foundation.
Both tenors admit that this is in fact a first ‘proof’ of the genome. There are still spelling errors here and there and some pages of the genomic book are not yet fully readable. Three more years of work are needed to complete and improve all the missing pieces. The main part, more than 95% and the most interesting areas for the geneticist, are now known. Both groups will publish their data in a leading scientific journal in the autumn. This press conference marks the end of one of the most prestigious scientific projects of the last fifty years.
The human genome, or the instruction book of biological life, is present in each of our more than ten thousand billion cells. The physical carrier of these instructions is deoxyribonucleic acid or DNA for short. It is a molecule that consists of only four chemical building blocks or bases, which we abbreviate with the letters A, T, G and C. The four bases follow each other in an endless chain. As the letters in this text form words, lines and sentences, the four letters of the DNA alphabet form instructions or genes. The amount of successive bases in each human genome is gigantic: more than three billion. To give you an idea: if you were to write out all the letters of the human genome in a format similar to the last edition of ‘Van Dale’s Great Dictionary of the Dutch Language’, you would get a book of 290,698 pages (the three parts of Dale together ‘barely’ count 4295 pages).
However, the human genome is not the first fully deciphered genome. Previously, the genome of about thirty bacteria, as well as that of baker’s yeast (Saccharomyces cerevisiae), the fruit fly (Drosophila melanogaster), the nematode (Caenorhabdidis elegans) and the rice plant (Oryza atival cracked.
Battery supercomputers
Partly due to the contribution of the company Celera, which only threw itself into the battle for the human genome in September 1999, the determination of the sequence of the human genome has gained momentum. From the beginning, Celera applied a faster but daring technique known as ‘shot gun’ sequencing. Celera first determined the sequence of a large collection of short DNA fragments, after which a battery of supercomputers fitted all the short pieces of sequence together. Celera did the same earlier with the sequence of the fruit fly. Instead of this ‘bottom up’ technique, the HGP used a ‘top down’ approach. Before determining the sequence of a piece of DNA, the researchers first found out where that piece was located on the genome. This required more work, but the HGP scientists found their approach more certain.
Celera appears to be the victor in this duel; yet independent observers claim that Celera would not have cleared it alone without the HGP. Over the years, HGP placed all its sequence information on the web, and Celera has gratefully made use of it.
At the press conference, Venter and Collins were in full agreement that there is actually no winner because the elucidation of the human genome is too important to be spoiled by an ‘Ike-first’ fraternal quarrel. Collins says decryption is not an end station, but the beginning of a new way of doing biomedical research. However, before we have dissected all interactions between genes, gene products and gene environment, it will probably already be the next century.
Yet the human genome provides a mass of new information that allows us to better understand, diagnose and ultimately treat diseases and disorders. According to Venter, with the sequence of the human genome in hand, scientists will pave the way for a new revolution in medicine: “the medicines we use today will resemble medieval anachronisms in fifty years’ time,” he says. Mihael Polymeropoulos of Novartis says that pharmaceutical and biotechnology companies are already focusing a large part of their research efforts on genomic interpretation research, and this will only increase in the future. Polymeropoulos continues, “the race to decipher the human genome is only small beer compared to the race to understand the genome. The decryption was a local American championship, understanding the genome is something like the Olympics,”
According to Gerald Rubin, geneticist at the University of California, Berkeley, it is a problem that the genetic code is only written in four letters and no one really understands how to read them. Only 3% of the three billion base pairs in the human genome actually code for genes. The rest of the DNA, by the insiders also labeled as ‘junk’, does not really have a function. Because the genes and proteins they encode are key to new medical treatments, there’s “gold in that three percent for whom it can be traced,” said Elliot Segal, a senior officer at pharmaceutical giant Bristol-Myers Squibb Co in a Newsweek interview.
‘Life-style’-program
However, the genes themselves are not the only important thing we will find in DNA. We will also learn why we are different from one another. Our DNA is more than 99% identical and yet we are so different from each other. Julia Roberts is prettier than Margaret Thatcher, but Thatcher is more intelligent than Roberts?
Most of the genetic variations are in non-coding DNA, so they have little or no effect. However, we also find differences in the genes themselves. Some of them lead to a modified protein while others change the expression pattern of the protein. It is these small differences that make us unique. Already scientists have catalyzed thousands of variations in our DNA and many thousands more will follow.
According to Craig Venter, in the near future it will even be possible to know your personal genetic code completely. It would fit perfectly on a CD, for example. From that information, your doctor will be able to determine your individual genetic risk for cardiovascular disease, cancer and numerous other conditions. Vincent Dauciunas of biotech company Agilent Technologies Inc. enthusiastically complements Venters’ prediction of the future by arguing that, based on your genetic pattern, the physician will give you customized, individualized medication. Your illness will then be treated optimally, taking into account your sensitivities to possible side effects of the medicine. If you take on a medical coach, who prescribes a life-style program adapted to your genetic pattern, you easily turn 120. We suspect this last one is a joke by Dauciunas.
Peter Raeymaekers