地域环境是塑造人体肠道微生物的主导因素

肠道是人体最大的微生物菌库，肠道微生物的群落结构和功能改变会影响人体的免疫和代谢系统，与多种疾病的发生和发展有关。宿主的遗传、年龄、性别、疾病状态、用药、激素水平、生活环境、地域、饮食和生活习惯等均会不同程度地影响人体肠道稳态。饮食和生活习惯不仅会在短期内塑造肠道菌群，长期来看也是调整和干预肠道菌群最有效的方式。有研究认为肠道微生物差异始于宿主基因，但最新的一项研究发现，宿主基因型仅可解释个体间微生物差异的1.9%， 而生活在同一地域环境中、饮食和生活习惯相近的人，其肠道菌群组成和功能更加相似^1]。一项中国人群的研究中也证实了地域是决定肠道菌群特征的决定性因素^2]。这一方面提示我们在进行肠道微生物与疾病的临床干预性研究中应充分考虑宿主生活的地域环境、饮食和生活习惯，另一方面也提醒我们进行地域特异性肠道微生物研究的重要性和价值。我国幅员辽阔， 地域丰富，民族众多，但目前我国的肠道微生物研究多集中在东南沿海等发展程度较高的城市，在西北地区却相当缺乏。 我国西北地区地处高原地带，高海拔，低氧压，昼夜温差大，造就了独特的生活环境、饮食文化和风俗习惯，在当地生活着包括藏、回、东乡、裕固等多个少数民族的人群，因此进行我国西北地区少数民族人群肠道微生物的研究对探究特定地域环境和饮食生活条件下人群的健康和疾病发生及发展具有重要价值，同时，也有助于寻找新的疾病治疗菌株，为地域性高发病和疑难杂症等的预防和诊治提供基于肠道微生物的参考^2]。

The regional environment dominates in shaping human gut microbiota

The gut is the largest microbial habitat in the human body. Gut microbial structural and functional changes were related to the occurrence and development of a variety of diseases in human, particularly the metabolic and autoimmune diseases. Multiple factors including host age, regional environment, region, dietary habits and lifestyle, diseases, drugs, hormone levels can all affect the gut microbial homeostasis. Dietary habits and lifestyle not only shape the gut microbiota in the short term, but also the most effective methods to regulate gut microbes for long. Gut microbial differences were reported to derive from the host genetics, but a recent study have showed the individuals living in the same environment, sharing similar dietary habits and lifestyles have more similar gut microbial composition and function rather than host genetics since it only explain 1.9% differences between individuals^1]. He et al also reported that the regional variation is the main factor to affect the gut microbiome in a Chinese cohort^2]. These results on the one hand suggest that the regional environment, dietary habits and lifestyle should be fully considered in the gut microbial studies, especially in those clinical intervention study, onthe other hand, it also reminds us of the importance and value of studying regional specific gut microbiota. China is a vast country, rich in regions and numerous nationalities. However, the gut microbial research in China hitherto is mostly concentrated in the southeast coastal cities, which is quite scarce in northwest China. The northwest China located in the plateau region with high altitude, low oxygen pressure and large variations in the temperature between day and night, which have created a relatively unique living environment, dietary habits and lifestyles. Plentiful of ethnic minorities have lived in the northwest China, such as Tibetans, Hui, Dongxiang, Yugu, etc. Therefore, it is of great value to study the gut microbiota of the minority populations in northwest China, not only to explore the relationship between health and diseases in the population under specific regional environment, dietary habits and lifestyles, but also helps to find novel strains to decrease the incidence of highly lethal local diseases and miscellaneous diseases in other regions based on the gut microbiota^2].