Human genome project, when researchers managed to sequence the DNA

The DNA structure was discovered the February 28, 1953 from James Watson And Francis Crickthanks to the data obtained by the famous Photo 51 Of Rosalind Franklin. This discovery, which earned the Nobel Prize for Medicine in 1962 to Watson and Crick, marked a turning point in molecular biology, opening the way to the study of genomeor the complete set of the genetic information of an organism. The Human genome projectstarted in the United States in 1990had the aim of mapping and sequencing human DNA. The project involved public and private bodies, including the National Institutes of Health (Nih) and the Celera Genomics by Craig Venter. The sequencing of the 3 billion couples of DNA bases, completed in 2003revealed that the human genome contains “only” 28,000-30,000 genesmuch less than the 100,000 initially estimated.

What is the human genome project: origins and objectives

The human genome project, started in 1990 and ended in 2003had the aim of deciphering the complete sequence of human DNA for the first time. In 1989, the Department of Health and Human Services of the United States founded the National Center for Human Genome Research (Nchgr) to support the project. Initially directed by James Watsonone of the discoverers of the DNA molecular structure, the direction then passed to Francis Collinsa geneticist expert, who led the project until his completion. The plan included a duration of 15 years, with objectives defined for the first 5 years and subsequently renewed.

To this milestone, however, it came after several technical difficulties, which led to a competition between theInternational Human Genome Sequencing Consortium – the consortium of international public bodies led by Collins – and the private company Celera Genomicsfounded in 1998 by Craig Venter. Beyond the competition between public and private research, both methods have contributed enormously to the advancement of the human genome project.

Not starting from a hypothesis to be verified, but exploring an unknown biological territory, has made it possible extraordinary discoveries achieving several secondary objectives. Among these, the sequencing of genomes of model bodieslike the bacterium Escherichia coliyeast Saccharomyces Cerevisiaethe fruit midinum Drosophila melanogasterthe nematode Caenorhabditis elegans And the mouse.

How the researchers mapped human genes

The human genome project was possible thanks to the collaboration of thousands of researchers internationally. In the United States, the Department of Energy (Doe) and the National Institutes of Health (NiH) financed the project with an estimated initial investment of approx 3 billion dollars for 15 years of research. Although the exact calculation is complex, this figure is considered a reliable estimate. The sequencing of the genome involved scientists from 20 universities and research centers in the United States, the United Kingdom, France, Germany, Japan and China, gathered under the International Consortium for the sequencing of the human genome. Despite the high cost, the economic impact of the genomics in the following decades has widely rewarded the investment, with direct benefits in the sectors pharmaceutical, biotechnology and medicalgenerating innovations and new industrial opportunities.

Sequeniation DNA means determining the precise order of the bases – Adenina (A), Timina (T), Guanina (G), Cytosine (C) – which form the segments of the molecule.

The public consortium has mainly made use of the method of Sanger sequencingimproved with technical innovations. This method works by replicating fragments of DNA and interrupting them in specific points with Dideossinucleotidi (DDNTP), which block the synthesis of DNA. Analyzing the length of the fragments with automatic sequenies and fluorescent dyes, it is possible to reconstruct the sequence. In the human genome project, the efficiency of this method has been enhanced thanks to Automated tools and advanced software to assemble the sequences.

The Shotgun methodon the other hand, used by Celera Genomics, it is faster and provides for the random fragmentation of the genome in small segments allowing you to directly sequence these fragments and then reconstruct the complete sequence via Advanced IT algorithms. Both methods played a key role in the success of the human genome project: the public consortium has followed a more methodical and accurate approach, while Celera privileged the speed, although initially with a lower degree of precision.

The sequence of the human genome generated by the project was a DNA mosaic from different people, whose identities have been maintained anonymous To ensure privacy. Most of the reference genome (about 70%) were sequential by a mixed descent individual, while the remaining 30% came from other 19 individuals, mainly of European origin. To collect DNA, the researchers recruited volunteers through public ads. The donors, largely from Buffalo, New York, provided blood samples, from which the DNA was extracted, after informed consent.

What were the most important discoveries about DNA thanks to the human genome project

In June 2000, theInternational Human Genome Sequencing Consortium announced the first draft of the sequence of the human genome, covering about the 90% of the total. Some particularly complex or highly repetitive regions were difficult to decipher with precision, which is why this preliminary version had over 150,000 gaps, i.e. traits of DNA whose sequence could not be determined with available technologies. The American president Bill Clinton He held a ceremony in the White House to announce this result to which politicians, ambassadors, scientists and journalists were present.

Finally, the April 14, 2003 The Consortium announced the completion of the human genome project and released a more complete and accurate version of the genome, which covered the 99% of the total sequence and reduced the number of gaps to less than 400. The accuracy of the final sequence is significantly improved compared to the initial draft, with a reduced error rate from 1 per 1000 bases to one every 10,000 bases.

The study revealed that the human genome contains among the 28,000 he is 30,000 genes, i.e. regions of DNA capable of allowing protein synthesis (and this is about the 2% of total human genome), a number well less than 100,000 Initially estimated, it has had important implications for biology and medicine. This has highlighted a fundamental aspect: the complexity of the human being does not depend on the quantity of genes, but their interactions and the regulation of the same. Most of this regulation takes place in DNA non -coding (i.e. that does not allow the synthesis of protein, about 98% of the total DNA), which, although initially considered “garbage”, actually plays a crucial role in managing gene expression.

After almost 20 years, the March 31, 2022the Consortium Telomere-to-nomere (T2T) He announced that he had completed the entire sequence of the human genome, eliminating all the gaps left and providing for the first time a complete and continuous map of our DNA. A maxi-team of scientists from universities and research centers from all over the world managed to “decipher” and map the8% of genome that was missing from the appeal, adding those pieces of the puzzle that did not allow researchers to have an overview of the human genetic code.

Overall, in addition to having opened the way to the study of Omic sciences – disciplines that use analysis technologies for the production of a large number of useful data for the study of a biological system – the project has changed the way of doing research in the world. Scientists made public the sequences of the human genome as soon as they were produced, thanks to the so -called Bermuda Principlesestablished during two meetings on the island. These principles have set the rules for the rapid issue of datapromoting the Open sharing information and increasing the awareness in biomedical research. This agreement was one of the most significant legacy of the project.

In addition, the HGP was an example of success of the so -called big sciencefacing technological challenges that have requested the collaboration of Interdisciplinary experts From all over the world, with work concentrated in a few centers to optimize resources. All this has revolutionized genetics and biomedicine, allowing progress in the diagnosis and treatment of genetic diseases, in the development of personalized medicine and in faster and cheaper sequencing technologies.