Give blood, make bug type.
"It is an important step forward," said Rob Knight, biologist at the University of Colorado, who was not involved in the research. "It is the first sign that human gut can get distinct types of ecosystems."
The research team, led by Peer Bork of the European Molecular Biology Laboratory in Heidelberg, Germany, found no passage between them, the European, American and Japanese topics, who studied they call Enterotypes and ethnic background.
She also found a connection to gender, weight, health or age. You are now others explore explanations. One possibility is that young children are randomly colonized microbes by ground-breaking types of gut. The microbes modify intestine so that only certain types can follow them.
Regardless of the cause of the various Enterotypes, you can end up with discrete effect on people's health. Good microbes aid in food digestion and synthesize vitamins, with enzymes that can make our own cells.
Dr. Bork and his colleagues have found that a unique balance of these enzymes makes all types. Enterotype 1 produces more enzymes for making vitamin B7 (also known as biotin), for example, Enterotype 2 more enzymes for vitamin B1 (thiamine).
The discovery of blood groups A, B, AB and o had on significant effects such as doctors medicine practice. She could limit the opportunities that the bodies of patients refuse a blood transfusion, by ensuring that the donated blood of a suitable type was. The discovery of the Enterotypes could own one day to medical applications, but it would be far down the road.
"Some things already are pretty obvious", said Dr. Bork. Doctors rules according to the people of Enterotypes, diets or drugs such as can adjust.
Or he speculated, doctors can find may be Enterotypes alternatives to antibiotics, which are increasingly inefficient. Instead of trying to eliminate disease-causing bacteria, the ecological balance of the aid have disturbed intestines, they could try to provide reinforcements for the good bacteria. He said "You would try the type restore, which you had above". Dr. Bork notes that more testing is required. Researchers must after Enterotypes in people from Africa, to look for Chinese and other ethnic origin. He also notes that so far, all themes come from developed countries, and to similar food to eat. "This is a shortcoming," he said. "We have not remote villages."
The discovery of Enterotypes follows on years of work mapping the diversity of microbes in the human body - the human Microbiome, as it is known. The difficulty of the task was staggering. Any person protects approximately 100 trillion microbes. (For comparison: the human body consists of approximately 10 trillion cells.) But scientists can not back a large majority to identify these bacteria in their laboratories it and learn its properties.
As genetics developed, scientists learned how to study the Microbiome through the analysis of the DNS. Scientists extracted DNA fragments of skin, saliva and stool. They learned how to recognize and discard the human DNA, so they were left Microbiome with genes from the. You searched for by the remaining DNA for all variants of a particular gene and compared them with known species. In some cases the variants was of familiar bacteria such as E. coli. In other cases, the gene was a kind of new science.
These studies provided insights into a variety similar to a rain forest. Different regions of the body were with different combinations of species. Scientists found more enormous diversity from one person to another. Many of the species who lived in a person mouth, were missing, for example, from another ' s.
Scientists would demand, if deeper studies show a unit on human Microbiomes. Researchers of the genome have identified in recent years, - the complete catalog of genes - hundreds of microbe species that live in people. They can compare now any gene that genomes can be found with this reference. You can determine the gene function, and which is part of the germ bacteria of the genus. And by counting all the genes, which can be found, the scientists can estimate how any kind of bacteria is.
In the recent work Dr. Bork and his team carried out an analysis of the gut microbes in 22 people from Denmark, France, Italy and Spain. Some of their subjects were healthy, while others were suffered in the obese or intestinal disorders such as Crohn's disease. Dr. Bork and his colleagues searched for fragments of DNA, the genome 1.511 of different species of bacteria is equivalent to. The researchers combined the results with previous studies of 13 Japanese people and four Americans.
Then, the scientists searched for patterns. "We have no hypothesis," said Dr. Bork. "Everything that came out was new."
Nevertheless, Dr. Bork was alarmed by the results of the study: all Microbiomes fell neatly into three separate groups.
And, as Dr. Bork and colleagues reported on Wednesday in the journal nature, each of the three Enterotypes was composed of various kinds to balanced also. People with type 1, had such as high levels of bacteria called Bacteroides. In type 2 Bacteroides were relatively rare, on the other hand, while the genus Prevotella was unusually common.
"You can cut the data in many different ways, and you get still these three clusters," said Dr. Bork.
Dr. Bork and his colleagues found confirmation of the three Enterotypes, when she turned to other Microbiome surveys and the groups continue to keep so far, they have expanded their own study on 400 people.
This article was revised and according to the following correction:
Correction: April 20, 2011
An earlier version of this article distorted the number of microbes relative to the number of cells in the human body. Any person protects approximately 100 trillion microbes, not 10 trillion, and is composed of about 10 trillion cells, not one million.
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