Community heterogeneity scaling of gut microbiomes across Chinese ethnicities and lifestyles appears invariant

In microbiome research, community heterogeneity of microbiota holds significant theoretical and practical implications, with both microbiome diversity and inter-subject heterogeneity being central objectives of the Human Microbiome Project (HMP). While diversity analysis, such as Shannon entropy, has become a de facto standard in microbiome studies, heterogeneity has been less frequently examined. However, this does not imply its lesser importance; rather, research in macrobial ecology has shown that heterogeneity can be equally, if not more, critical in determining community stability—a concept closely related to microbiome dysbiosis, which significantly impacts microbiome-associated diseases. The challenge in addressing heterogeneity lies in its complexity, as it accounts for species interactions beyond simple species counts. In this study, we applied Taylor’s Power Law (TPL) and its extension (TPLE) to analyze gut microbiome heterogeneity among Chinese populations across various ethnic groups and lifestyles, utilizing a dataset of 314 individuals representing seven ethnicities and two lifestyles (rural and urban). Our findings indicate that community heterogeneity scaling across individuals is invariant to lifestyle and geography/ethnicity, described by a consistent scaling model (TPLE) applicable at four taxonomic levels (phylum, family, genus, and species). Additionally, at the microbial species level, TPL’s population aggregation parameter is invariant at higher taxonomic levels (phylum and family) but varies at lower levels (genus and species). These results suggest that inter-individual heterogeneity scaling among Chinese ethnicities and lifestyles is shows a high degree of stability, potentially shaped by biogeography, culture, and genetic backgrounds. This stability presents an analogy to quasi-invariant properties in physical systems.