The map shows how the human genome has changed in the world – Hypertext

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What makes us different? What genetic changes occur among populations of sub-Saharan Africa, Southeast Asia or Latin America? In 2008, the Project 1000 Genomes was driven with the objective to know the variability of the human genome over the entire planet. Project 1000 Genomes has managed to catalog the genetic codes that distinguish one individual from another

genome of the human race is made up of 3,000 million base pairs or “letters” different. Millions of those letters change the DNA of one person to another, but what happens at the population level? Is it possible to map the human genome variability from one point to another planet?

A consortium of researchers, led by European Molecular Biology Laboratory , published today two articles in Nature that help to understand the genetic variation observed in 26 populations around the world. When the 1000 Genomes Project started, the purpose was to sequence the DNA of at least a thousand individuals, but scientists have managed to go a step further, cataloging 2,504 genomes of five continental regions of the world (South and East Asia, Europe, Africa and America) .

The largest catalog of genetic differences

In the first study, a team led by Adam Auton analyzed small variations occurring in the genome of these 2,504 people. The goal was map the changes of up to 500 “letters” that occurred in your DNA in order to check whether there were differences between populations.

As expected, changes most frequent genetic they are affecting a single “letter” or DNA base. Auton group achieved characterize 88 million genetic variants of this type, in addition to 3.6 million mutations in the form of insertions or deletions and 60,000 structural changes affecting large parts of chromosomes .

The largest catalog of genetic differences to date has also helped shed light on the own development human. In that sense, those individuals who had ancestors in Africa had a larger number of areas of DNA that changed. By contrast, other people showed greater variability in the number of variants, which in turn was proportional to the degree of descent of African origin.

The variation among human populations

The second article, published in the journal Nature , reveals the structural changes observed in 2,504 individuals. This second type of changes are related to variations in DNA that affect large portions of the genome, with a size that can reach 500,000 bases or “letters”. Thanks to advances in techniques sequencing , mapping these gene changes have been made in more detail and accuracy than ever.

These structural variations are plentiful, researchers say , and they occur as a result of much more complex than previously thought evolutionary processes. The second type of account also labeled with a “disproportionate impact” on gene expression in the words of team Jan Korbel, given the small number of structural changes that are usually observed in comparison with the first job changes.

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The set of variants analyzed, for example, may show why some populations of Tibet seem more resistant to high. Or perhaps help us to understand why some Mexican populations have increased risk of obesity. Changes written in our DNA have now been cataloged by the 1000 Genomes Project, an initiative with which we can understand the prevalence of certain diseases in certain regions or features that differentiate populations from one another.

Knowing the huge variability of the human genome at the individual level and map changes in different populations seemed a titanic challenge back in 2008. Seven years later, the catalog published today in Nature it is just the end of the 1000 Genomes Project, whose data have been published in open. But actually it marks the beginning of a much bigger: to understand the genetic keys that differentiate one individual from another, regardless of the region where you live and part of the world where applicable

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