BCM Human Microbiome Projects to Sequence 150 Bacteria, Sample Human Metagenome
News Nov 06, 2007
A $2.3 million grant from the National Human Genome Research Institute will enable researchers at the Baylor College of Medicine Human Genome Sequencing Center in Houston to determine the genetic code of bacteria that colonize healthy humans and study the structure of microbial communities from five regions of the human body.
The grant is part of the first phase of the Human Microbiome Project, a Roadmap initiative of the National Institutes of Health, which will request proposals for sequencing individual bacteria that normally inhabit various parts of the human body as well as metagenomic sequencing of the communities that these bacteria create.
The Roadmap grant adds to ongoing pilot Human Microbiome Projects at the BCM Human Genome Sequencing Center, supported by the National Human Genome Research Institute, one of the National Institutes of Health. Altogether the microbiome activities will produce reference sequences for 150 bacteria and sample the communities from the gut, vagina, skin, mouth and nose.
"The Human Microbiome Project seeks to describe the microbial community that colonizes you," said Dr. George Weinstock, co-director of the BCM Human Genome Sequencing Center and principal investigator of its bacterial sequencing activity. "It also seeks to understand how this community changes and correlate those changes with health, disease and new opportunities for early diagnosis."
The project also provides opportunities for new treatments and therapies that are either preventive or reactive to disease, said Weinstock, who has been a leader in developing this research area.
"That's the whole idea of probiotics – manipulating your microbial communities," he said. The studies could lead to new understanding of a host of diseases – even some kinds of cancers.
In many ways, the Human Microbiome Project is more ambitious than the Human Genome Project was at the beginning.
"Next generation DNA sequencing technology, which enables us to produce genetic sequences quickly and accurately, has finally reached a state where such a large project is possible," said Dr. Richard Gibbs, director of the BCM Human Genome Sequencing Center.
The effort will start with determining the genetic sequence of various bacteria that colonize humans, he said. Then researchers plan to look for variation among individuals and populations.
"Are there different types or combinations?" said Weinstock. "Is there one type of flora in this group of people and another in a different group?"
Then the project will transition into metagenomics – determining the genetic sequence of communities of bacteria that colonize human beings.
"We are colonized by thousands of species of bacteria," said Weinstock. "There are only 20,000 or so genes in my genome and all my cells have the same genes. Each bacterium has on the order of 1,000 genes, but there are thousands of species of bacteria and each has different genes. That means there are millions of bacterial genes in you. Collectively, they are a metagenome. You carry them with you, and the activity of their genes affects you. We want to do the DNA sequencing on the community itself."
"One of the major selective forces in all evolution has been micro-organisms," said Weinstock. "Nothing has happened in evolution that didn't have microbes crawling all over it."
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