More on the microbiome from the innovative Gladstone Institutes (discoverers of fibrinogen's ability to initiate the MS disease process). We're just beginning to understand bacteria.
"...simply categorizing the kinds and amounts of bacteria present in the body is not enough—the genetic make-up of each strain also needs to be decoded. The DNA within the same species of bacteria from two different human hosts can be wildly different. While the genomes of two humans may only vary by 0.1%, two strains of the same bacteria can differ by more than 50%—greater than the disparity between the genomes of humans and mice. What’s more, the variations in bacterial DNA are often important pieces that are involved in things like antibiotic resistance or the digestion of dietary fiber."

The most influential “organ” in the human body is made up of foreign cells—six pounds worth of microorganisms. Katherine Pollard studies the human microbiome to learn how it influences health and disease.