Gut microbiota features of the geographically diverse Indian population

Abstract

Population-level microbial profiling allows for identifying the overarching features of the microbiome. Knowledge of population specific base-line gut microbiome features is important due to the widely reported impact of geography, lifestyle and dietary patterns on the microbiome composition, structure and function. Here, the gut microbiota of more than 1000 subjects across the length and breadth of India is presented. The publicly available 16S rRNA gene profiling data of faecal microbiota from the Landscape Of Gut Microbiome - Pan-India Exploration (LogMPIE) study representing 14 major cities, covering populations from northern, southern, eastern and western part of India analyzed. Majority of the dominant OTUs belonged to the Firmicutes, Bacteroidetes and Proteobacteria phyla. The rarer fraction was comprised of OTUs mainly from the phyla Verrucomicrobia and Spirochaetes. The median core size was estimated to consist of 12 OTUs (>80% prevalence) dominated by representing genera Prevotella, Faecalibacterium, Bacteroides, Roseburia, Megasphaera, Eubacterium and Gemmiger. Geographic location explained majority of the variation in the gut microbiota community structure. The observations of the present study support the previous reports of Prevotella dominance in the Indian population. The Prevotella/Bacteroides ratio was high for the overall population irrespective of geographic location and did not correlate with BMI or age of the participants. Despite a rapid transition towards a western lifestyle, high prevalence of Treponema in the Indian gut microbiota suggests that the urban population still harbors signatures of the traditional gut microbiome. The results presented here improve the knowledge of baseline microbiota in the Indian population across the length and breadth of the country. This study provides a base for future studies which need to incorporate numerous other confounding factors and their impact on the observed characteristics of the Indian gut microbiome.