You have unique fingerprints, and unique DNA sequences in your genome. So what else in your body is unique to you? Weird as it sounds, genomics has shown that trillions of microbes grow in nearly every part of your body. These bacteria, fungi, viruses, and mites outnumber your human cells by 10 to 1. Microbial communities vary from person to person and from one part of your body to another. We pick our microbes up from our family, pets, food, and environment, and they change constantly because of travel, illness, aging, and day-to-day life.
The communities of microbes living in and on the various parts of your body make up your microbiome. They help you digest your food, offer protection against dangerous bacteria and viruses, and keep your immune system responsive to your environment and running smoothly. Maintaining a healthy microbiome is very important: In fact, changes in the microbiome may even contribute to the onset of diabetes, obesity, and other disorders. Because our microbiome’s state often differs in health and disease, researchers predict that understanding a person’s microbial community will help doctors treat patients by working to return their “out of balance” microbiomes to normal again.
Changes in the microbiome may contribute to the onset of diabetes, obesity, and other disorders
Like all living things (and viruses, which aren’t really alive), the microbes in your microbiome have their own genetic material, which contain their “how-to” instructions. Scientists in the Human Microbiome Project funded by the National Institutes of Health swabbed and scraped different parts of the body and used DNA sequencing technology to directly study the microbiomes of nearly 250 healthy people. Some of the microbial species that were found on an individual’s body could not be grown outside of the human body – before genomic sequencing, we never knew they existed. But because of genomics, we now know that these undiscovered microbes are living happily in noses, underarms, and elbow creases.
Image courtesy of Darryl Leja, NHGRI