MICROBIOME SYMBIONTS. “Metagenomic sequencing has shown that each human gut has entered into a persistent partnership with over 150 species of bacteria, and that the human species maintains about 1000 major bacteria groups in our gut microbiome. The gene set contained by this symbiotic metagenome is about 150 times larger than that of the human eukaryotic genome. And this does not include the symbionts of human airways, skin, mouth, or reproductive orifices.”