MICROBIOME STUDIES. “While we are accumulating large metagenomic datasets and cataloguing bacterial genomes that make up the different parts of the human microbiome in normal and diseased individuals, it is still very difficult to connect the presence or change in frequency of specific bacterial species with the associated phenotypes.”
https://bmcsystbiol.biomedcentral.com/articles/10.1186/1752-0509-8-S2-S1