PHILADELPHIA —The digestive system is home to a myriad of viruses, but how they are involved in health and disease is poorly understood. In a study published online this week in Genome Research, researchers from the Perelman School of Medicine at the University of Pennsylvania, have investigated the dynamics of virus populations in the human gut, shedding new light on the gut “virome” and how it differs between people and responds to changes in diet.
“Our bodies are like coral reefs, inhabited by many diverse creatures interacting with each other and with us,” said Frederic Bushman, PhD, professor of Microbiology, and senior author of the study The interactions between viruses, bacteria, and the human host likely have significant consequences for human health and disease, especially in the delicate ecosystem of the gut microbiome.
In this work, lead author Sam Minot, Bushman, and other members of the research team investigated the dynamics of the gut virome during perturbations to diet. The group studied six healthy volunteers--some received a high fat and low fiber diet, others a low fat and high fiber diet, and one an ad-lib diet.
By analyzing DNA sequences from viruses and bacteria present in stool of the volunteers over the course of eight days, they found that although the largest variation in virus diversity observed occurred between individuals, over time dietary intervention significantly changed the proportions of virus populations in individuals on the same diet, so that the viral populations became more similar.
“The study provides a new window on the vast viral populations that live in the human gut, demonstrates that they vary radically between individuals, and shows that dietary changes can affect not just bacterial populations but also viral populations,” Bushman said.
This work was supported by the Human Microbiome Roadmap Demonstration Project, the Pennsylvania Department of Health, the National Institutes of Health, and the Molecular Biology Core of The Center for Molecular Studies in Digestive and Liver Diseases.
Penn Medicine is one of the world's leading academic medical centers, dedicated to the related missions of medical education, biomedical research, and excellence in patient care. Penn Medicine consists of the Raymond and Ruth Perelman School of Medicine at the University of Pennsylvania (founded in 1765 as the nation's first medical school) and the University of Pennsylvania Health System, which together form a $4.3 billion enterprise.
The Perelman School of Medicine has been ranked among the top five medical schools in the United States for the past 17 years, according to U.S. News & World Report's survey of research-oriented medical schools. The School is consistently among the nation's top recipients of funding from the National Institutes of Health, with $392 million awarded in the 2013 fiscal year.
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