In 2019, the international project that seeks to sequence and map all human genetic variation began, called the Human Pangenome Reference Consortium (HPRC), and funded by the United States National Human Genome Research Institute.
Last May, an international team of researchers presented the first draft of the human pangenome, the most complete genetic map of the human being to date, which contains the complete genetic sequence of 47 people from different parts of the world, revealing detailed information about 94 complete genomes. This new pangenome has discovered up to 1,115 new duplications, adding about 119 million bases (letters) to the human genome, which contains 3.3 billion paired bases, with more than 99 percent of those bases being the same in all people.
DNA bases are grouped in pairs, A with T and C with G to form units called base pairs, genes are small sections of DNA, which constitute the basic functional and physical units of genetic inheritance.
The genome is the total DNA sequence that an organism has, which, in the case of humans, is estimated to be made up of about 25,000 genes. The genome available so far was from a white individual of Caucasian origin, with no genetic information associated with other ethnicities.
The first draft of the human genome sequence was published in the year 2000, in April 2003, the final results of the Human Genome Project were released, constituting an enormous advance in the knowledge of human biology, which has served in the last two decades to study diseases that have a genetic basis, among other applications.
In the work carried out to obtain the last human pangenome, researchers have discovered a genetic structural variant, this is a change in the structure of DNA that does not imply a change in the nucleotide sequence. Structural variants can be of many types, but those currently identified are produced by insertions, deletions, translocations or inversions, that is, the sequence has been added, deleted, exchanged or inverted at a certain time and place in the DNA chain. .
Structural variations can be caused by a variety of factors, including errors during DNA replication, spontaneous mutations, and DNA damage.
Structural variants can have a significant impact on health. Some structural variants are associated with diseases, such as cancer, heart disease, and neurological diseases. Other structural variants may affect development and growth, or may increase the risk of certain diseases.
The study of structural variants is an area of active research. Researchers are working to better understand how structural variants affect health and to develop methods to detect and characterize structural variants.
The human genome sequencing procedure is a complex process that requires purifying and fragmenting the DNA so that it is suitable for sequencing. Subsequently, each fragment is subjected to sequencing techniques such as Sanger, DNA Chip sequencing, and they are subsequently aligned to form a map of the genome.
The purification process is carried out in order to eliminate proteins and other molecules. Subsequently, it is necessary to fragment it into chains of no more than a few hundred pairs by means of sonication or enzymatic hydrolysis, and then start sequencing techniques, the most modern of which are capable of performing several sequencing at the same time.
Despite these advances, it can be considered that the human genome has been completed since 2022. However, since the human genome is a structure in constant evolution, it can be said that it will never be complete.
The researchers responsible have aimed to obtain the complete sequence of 350 individuals by 2024.
