When science reaches a peak, it opens up a vast prospect of a further path to new peaks, new roads are opened along which science will go further.
S. I. Vavilov
One of the most mysterious and unusual molecules is DNA, the main molecule of life.
The search for the foundations of the living was long and difficult: with mistakes and hopes, with faith and disappointment.
And that's happened!
Between 1949 and 1951, biochemist Erwin Chargaff (1905-2002) and his group made a major discovery. They determined the quantitative ratio of purines and pyrimidines in DNA.
And in 1953, an article by Francis Crick (1916-2004) and James Watson (born 1928) was published in the journal Nature. They constructed the spatial structure of DNA on the basis of X-ray diffraction studies obtained by Rosalind Franklin (1920-1958) and Maurice Wilkins (1916-2004), as well as the Chargaff rule.
There was only one page of text, but it was with this publication that the era of Molecular biology began.
James D. Watson and Francis Crick revolutionized biology. The structure of DNA was no longer a mystery. It turned out that the molecule was built ingeniously simple, like everything that nature has created.
The structure of DNA is as follows: two antiparallel polynucleotide chains are twisted about the axis. On the periphery of the molecule there are carbohydrate-phosphate chains, inside – nitrogen-containing heterocycles.
The nitrogenous bases of one antiparallel chain are connected to a specific base of the other chain, observing Chargaff's rule: adenine combines with thymine, guanine with cytosine. This arrangement is called complementary.
But how does this molecule work?
It is known that one of the functions of DNA is the storage of hereditary information, which is contained in genes.
Therefore, the study of the coding part of human DNA makes it possible to understand the origin and development of many genetic diseases, including such as malignant neoplasms.
The development of these diseases is directly related to the work of genes.
The need for further study of this molecule would help to find a clue to the development of cancer. These and many other considerations led to the fact that scientists around the world decided to read human DNA: which nucleotides and in what sequence are located in the molecule, as well as the possible information embedded in them.
Therefore, it was too early to stop.
In 1990, it was officially announced the launch of a program to study the nucleotide sequence of all human DNA. The Human Genome has become an international research project in which many countries have participated.
Already in 2003, this work came to an end, but it was completed in 2022.
So, the difficult task was solved. But after reading the entire sequence of nucleotides, it did not bring clarity.
