The human genome, that is, our genetic information, has been completely decoded for 20 years. However, significant gaps and ambiguities remain. For example, the order in which the decoded parts of the genome belong together.
Scientists from California now want to fully determine the missing detail for the first time — and this time really!
2001 review: Until then, a similar report passed to the press. In fact, at that time, several research groups had only decoded 92 percent of the human genome.
Finally to the finish line with new technology
The fact that the remaining eight percent were missing due to technology is still insufficient.
the problem: If you want to identify DNA, you must break down the genetic material into its components beforehand. Then you have a puzzle in which the individual parts can be identified. However, it is very difficult to assemble it because there are many similar parts to each other.
This time, the researchers used two new, alternative techniques to conduct their investigations. In one, the DNA molecule was sequenced into larger pieces, while the other examined this sequence with a laser.
These new technologies are still not reliable on their own, but the group produced such a useful result. The number of DNA bases recorded was increased from 2.92 billion to 3.05 billion, which corresponds to an increase of 4.5 percent. The number of recorded genes increased 0.4 percent to 19,669.
Human geneticist: ‘This is a great scientific achievement’
It doesn’t seem like much at first, but is full decryption still a quantum leap? And what will this change in medicine?
“I’m not going to talk about a quantum leap, because that means going completely in a new direction, which is not the case here. But it’s a very respectable step forward, since you’ve penetrated areas of the DNA code that are difficult to analyze,” says Professor Dr. Wolfram Hen, a scientist Human Genetics at the University of Saarland and a member of the German Ethics Council.
“The research team managed to get into the most inaccessible parts of the desert because of our genetic makeup, but they didn’t flip everything upside down before and didn’t claim to either.”
But why has there been frantic work to completely decode the genome? Was 92 percent not enough?
No, says Professor Hein. And for several reasons:
“Perfect knowledge is first and foremost that satisfies human curiosity. On the other hand, we can assume that hard-to-reach regions of the genome are also responsible for switching regions that affect other genes. And if we can access them and see the whole context, we also have opportunities Better for the development and use of medical treatments.In order to be able to use the so-called genetic scissors, with which the genetic material of each cell can be precisely modified, one must first of all know exactly where to put it.Full decoding can help in the future “.
Can we all clone each other soon?
However, the genetics expert does not see that the researchers’ work will help us all to clone in the future.
Professor Henn on Bild: “Cloning has little to do with genetics because it is a reproductive medicine technique in which genetic information is taken unchanged. On the other hand, genetic engineering does not reproduce, but changes. So knowledge of the genome has relatively little effect on cloning. By decoding the control genes for early embryonic development processes, we will better understand how errors occur in cell division. These will be very important findings for cancer research, which could then lead to direct treatments.”
Treating rare genetic diseases thanks to gene therapy
But the researchers’ findings will not only play an important role in future medicine: there are already genetic diseases for which decoding the genome means the direct route to treatment, says Professor Hein.
“In the case of some hereditary muscle wasting diseases, direct gene therapy can help prevent further breakdown of muscle cells. Another example is Gaucher disease which has a metabolic defect, in which a specific enzyme is not produced. Through genetic sequencing, one learns what It is the enzyme that is already missing and can be produced artificially as an infusion. Decoding the genome eventually helped provide sufferers with very expensive but life-saving treatments.”
However, the previous areas of application are relatively rare genetic diseases, Hen continues.
“The vast majority of common diseases, such as cardiovascular disease or cancer, are multifactorial, which means that genes are usually just one of many factors that cause disease. For us to be able to cure here in the future, in addition to decoding the genome, There are some other building blocks missing, which we need to research further – for example on the interactions of different genes and external influences on our genes.”
Study has double
Despite the impressive results, it should be noted that these results have not been confirmed by independent experts. So far, the study has only been uploaded to the BioRxiv prepress server.
But what does this mean? So do we have to wait until we can really talk about a full decryption?
Human geneticist Hein is optimistic: Some well-known genetics experts are participating in the study. So I suppose it is serious work and that the reason the study was initially published as an introduction to print is a strategic approach to publication. Similar to how the polar expeditions were about who entered the area first. But one need not expect anything to be tossed or crushed while studying.”
However, there is one limitation, and the research colleagues themselves have pointed out this. So far, only one human genome has been fully worked out.
“In order to understand the differences between humans, one now has to analyze a variety of the human genome. But it is still a big step that has been taken here. In their investigations, the researchers even delved into the so-called centromers, which are related to cell division and which are difficult to break. Long way there. Respect!”