Human genome v.3.0
The genome expandedNikolay Gorodetsky, "Newspaper.
Ru»The new issue of the journal Nature published an article (Integrating common and rare genetic variation in diverse human populations), which describes the third version of the map of variations of the human genome, the study of which is carried out within the framework of the HapMap project.
New, but still interim results of the work report the study of seven new ethnic groups of people. Thus, their total number reached eleven.
Any two people are more than 99 percent genetically identical. But the remaining small part of the genetic material gives differences between people and explains, for example, individual susceptibility to diseases, different reactions to drugs or environmental factors.
Changes in the human genome (one such change is said to be due to single-nucleotide polymorphism) occur in the haplotype (this is a combination of genes on one chromosome). Within the framework of the HapMap project (short for haplotype map – haplotype map), just such changes are being studied.
In the previous two versions, four geographical population groups were studied: the Yoruba tribe in Ibagan (Nigeria), Japanese from Tokyo, Han Chinese from Beijing and residents of Utah (USA) with roots from Northern and Western Europe. A total of more than 3.1 million polymorphisms were analyzed for these four populations.
An article published Thursday in Nature reports the analysis of more than 1.6 million polymorphisms in eleven geographical groups. To the four that were worked on in the previous two versions, seven more were added: citizens of African descent from the southwestern part of the United States, the Chinese diaspora from Denver, Gujarati Indians from Houston, a group of Luhya peoples living in Kenya, the semi-nomadic Maasai people also living in Kenya, persons of Mexican origin from Los Angeles and Italians living in the province of Tuscany.
By its scale, this is the largest study of its kind conducted by mankind.
The increase in the amount of the material under study allowed scientists to identify genetic variations that occur quite rarely in humans, as a result of which they passed by the first two versions of HapMap. 77 percent of the polymorphisms found were new. Obviously, in addition to this, there are a huge number of variations.
In addition to a number of intermediate results, the researchers evaluated their ability to predict polymorphisms in other population groups based on HapMap data and found that this is quite possible for both general variations and for some rarer polymorphisms. Nevertheless, this does not mean that the current edition of the HapMap polymorphism map is exhaustive, if only because many rare variations are still beyond the attention of mankind and it is not known for sure how many such polymorphisms exist, but they may be responsible for various diseases. The more valuable is the work that has been and will be carried out within the framework of the HapMap project.
In addition, many researchers related to HapMap are also working on the global project "1000 Genomes" (1000 Genomes Project), which started in January 2008 and involves decoding the genomes of 1000 people from around the world.
"HapMap is a stellar example of how advanced technologies and dedicated work to obtain DNA samples from specific people in large populations allows us to obtain detailed data for the study of human diseases," said Richard Gibbs, one of the project participants and co–author of the article in Nature, director of the Center for Human Genome Sequencing at Baylor College of Medicine.
Portal "Eternal youth" http://vechnayamolodost.ru03.09.2010