Features | Partner Sites | Information | LinkXpress
Sign In
JIB
BioConferenceLive
GLOBETECH PUBLISHING

Baseline Clinical Data Established for the Human Microbiome Project

By BiotechDaily International staff writers
Posted on 11 Mar 2013
A recent paper described a significant advance in the effort to establish a rigorous clinically defined base for the "Human Microbiome Project.”

The microbiome is the totality of microbes, their genetic elements (genomes), and environmental interactions in a particular environment. The term "microbiome" was coined by the Nobel Prize-winning geneticist Joshua Lederberg, who argued that microorganisms inhabiting the human body should be included as part of the human genome, because of their influence on human physiology. The human body contains over 10 times more microbial cells than human cells, although the entire microbiome only weighs about 200 grams.

Investigators at Baylor College of Medicine (Houston, TX, USA) are among many collaborators working on the Human Microbiome Project. They coauthored a study in the March 2013 issue of the FASEB Journal that described the establishment of rigorous clinically defined criteria for the study of the microbiome.

They first screened potential 18 to 40 year-old participants using exclusion criteria based on health history, including the presence of systemic diseases (e.g., hypertension, cancer, or immunodeficiency or autoimmune disorders), use of potential immunomodulators, and recent use of antibiotics or probiotics. Subsequent physical examinations excluded individuals based on body mass index (BMI), cutaneous lesions, and oral health. Ultimately, they screened 554 individuals to enroll 300 (149 men and 151 women, mean age 26 years. They obtained specimens from the oral cavity, nostrils, skin, gastrointestinal tract, and vagina (15 specimens from men and 18 from women). The study evaluated longitudinal changes in an individual's microbiome by sampling 279 participants twice and 100 individuals three times. This sampling strategy yielded 11,174 primary specimens, from which 12,479 DNA samples were submitted to four centers for metagenomic sequencing.

In metagenomic sequencing, DNA recovered directly from environmental samples in an untargeted manner is analyzed using shotgun Sanger sequencing or pyrosequencing to recover the sequences of the reads. To determine the phylogenetic identity of a sequence, it is compared to available full genomes. One drawback of this approach is that many members of microbial communities do not have a representative sequenced genome. Despite the fact that metagenomics is limited by the availability of reference sequences, one significant advantage of metagenomics is that metagenomics data can elucidate the functional potential of the community DNA. Targeted gene surveys cannot do this as they only reveal the phylogenetic relationship between the same genes from different organisms. Functional analysis is done by comparing the recovered sequences to databases of metagenomic annotations. The metabolic pathways that these genes are involved in can then be predicted.

"While historically pre- and probiotics have dominated the microbiome landscape, emerging data from numerous labs as to the impact of dietary interventions and antibiotic exposure will play formative roles in tailoring therapy," said first author Dr. Kjersti M. Aagaard, associate professor of obstetrics and gynecology at Baylor College of Medicine. "We may find that the answers to our most common and prevalent health and disease states lies not in manipulating the human genome, but rather, in utilizing subtle shifts in diet and components of the diet, efficacy trials in prophylactic or preventative antibiotic therapies, and care attention to the over prescription of steroids and antibiotics."

Related Links:
Baylor College of Medicine


comments powered by Disqus

Channels

Drug Discovery

view channel
Image: Molecular rendering of the crystal structure of parkin (Photo courtesy of Wikimedia Commons).

Cinnamon Feeding Blocks Development of Parkinson's Disease in Mouse Model

A team of neurological researchers has identified a molecular mechanism by which cinnamon acts to protect neurons from damage caused by Parkinson's disease (PD) in a mouse model of the syndrome.... Read more

Therapeutics

view channel
Image: This type of electronic pacemaker could become obsolete if induction of biological pacemaker cells by gene therapy proves successful (Photo courtesy of Wikimedia Commons).

Gene Therapy Induces Functional Pacemaker Cells in Pig Heart Failure Model

Cardiovascular disease researchers working with a porcine heart failure model have demonstrated the practicality of using gene therapy to replace implanted electronic pacemakers to regulate heartbeat.... Read more

Lab Technologies

view channel

Precise Ion Irradiation Dosing Method Developed for Cancer Therapy

Scientists are employing nuclear physics principles to provide more effective approaches to radiotherapy treatment for cancer patients. Radiation therapy using heavy ions is best suitable for cancer patients with tumors that are difficult to access, such as in the brain. These particles scarcely damage the penetrated... Read more

Business

view channel

Cancer Immunotherapy Sector Predicted to Surge to USD 9 Billion Across Major Pharma Through 2022

The immunotherapy market will experience substantial growth through 2022, increasing from USD 1.1 billion in 2012 to nearly USD 9 billion in 2022 (corresponding to 23.8% annual growth) in the United Kingdom, United States, France, Germany, Italy, Spain, and Japan, according to recent market research. This notable growth... Read more
 
Copyright © 2000-2014 Globetech Media. All rights reserved.