The other microbiome

As recently as 2010, Forest Rohwer could be found immersed—literally—in the Pacific Ocean. Rohwer, a microbiologist at San Diego State University, has spent more than a decade researching the bacteria and viruses that inhabit coral reefs, developing ways to study the microbes, and asking how they interact with each other. Now he’s diving into a new territory that is prime for exploration: the viruses that call the human body home. His move comes at a time when there is growing interest in studying the so-called human virome, and the methods that Rohwer helped develop and fine-tune for studying marine microbes are now being applied to the human ecosystem. After all, the human gut isn’t all that different from a deep-sea community; it’s full of viruses and bacteria struggling to survive in a tough environment. Researchers have found that many of the viruses in the human gut are bacteriophages—like the six-legged structure shown here attached to a rod-shaped bacterium—and likely impact health indirectly through their effects on the bacterial population. ©iStockphoto.com/ktsimage. “Almost all of the techniques that are now used to study the human virome were developed for marine biology,” says Rohwer. Just as Rohwer used high-throughput genetic sequencing to describe coral reef microbe communities, he and others are now amassing data about which viruses live in the human body, how they differ between sick and healthy people, and how the virome changes over time. Rohwer, for example, has taken a census of the viruses inside the lungs of cystic fibrosis patients, and believes that they could influence the severity of the condition’s symptoms (1, 2). Cystic fibrosis is caused by a mutation in the gene encoding a protein that regulates the body’s mucus, The human virome is probably at least as important to human health as our …