Comparative Analysis of Gut Microbiota of Native Tibetan and Han Populations Living at Different Altitudes.

Kang Li,Yixiang Shi,Yi Ren,Luobu Gesang,Yuqiang Nie,Yanlei Du,Hong Wang,Yongjian Zhou,Zeng Dan,Andrea S Wiley

doi:10.1371/journal.pone.0155863

Abstract

The factors driving the composition of gut microbiota are still only partly understood but appear to include environmental, cultural, and genetic factors. In order to obtain more insight into the relative importance of these factors, we analyzed the microbiome composition in subjects of Tibetan or Han descent living at different altitudes. DNA was isolated from stool samples. Using polymerase chain reaction methodology, the 16S rRNA V1–V3 regions were amplified and the sequence information was analyzed by principal coordinates analysis and Lefse analyses. Contrasting the Tibetan and Han populations both living at the 3600 m altitude, we found that the Tibetan microbiome is characterized by a relative abundance of Prevotella whereas the Han stool was enriched in Bacteroides. Comparing the microbiome of Han stool obtained from populations living at different altitudes revealed a more energy efficient flora in samples from those living at higher altitude relative to their lower-altitude counterparts. Comparison of the stool microbiome of Tibetan herders living at 4800 m to rural Tibetans living at 3600 m altitude shows that the former have a flora enriched in butyrate-producing bacteria, possibly in response to the harsher environment that these herders face. Thus, the study shows that both altitude and genetic/cultural background have a significant influence on microbiome composition, and it represents the first attempt to compare stool microbiota of Tibetan and Han populations in relation to altitude.

Highlights

As the largest and most complex micro-ecosystem of the body, the gut microbiota and their metabolites play extremely important roles in protecting the intestinal mucosal barrier and maintaining human health [1,2,3,4,5,6]
The subjects belong to four groups: 1) 13 native Tibetan herders living at an altitude of more than 4800 m; 2) 13 native Tibetan peasants living at an altitude of 3600 m; 3) 12 individuals of the Han population who migrated to a high altitude and lived in Lhasa (3600 m) for over 20 years; and 4) 30 citizens of a low-altitude Han population who lived in the Chinese hinterland (Chengdu, Sichuan Province) at an altitude of about 500 m
Based on the 454 sequencing platform, all of the polymerase chain reaction (PCR) products from 16S rRNA V1–V3 regions of stool DNA from 38 subjects (13 native Tibetan herders living at an altitude of more than 4800 m, 13 native Tibetan peasants living at an altitude of 3600 m, and 12 Han individuals living on the plateau at 3600 m) were sequenced

Summary

Introduction

As the largest and most complex micro-ecosystem of the body, the gut microbiota and their metabolites play extremely important roles in protecting the intestinal mucosal barrier and maintaining human health [1,2,3,4,5,6]. In accordance with their function in aiding food digestion, the gut microbiota genome appears significantly enriched in genes that participate in the metabolism of carbohydrates, amino acids, vitamins, and short-chain fatty acids, and PLOS ONE | DOI:10.1371/journal.pone.0155863. In accordance with their function in aiding food digestion, the gut microbiota genome appears significantly enriched in genes that participate in the metabolism of carbohydrates, amino acids, vitamins, and short-chain fatty acids, and PLOS ONE | DOI:10.1371/journal.pone.0155863 May 27, 2016

Methods

Results

Conclusion