高原人群口腔和肠道宏基因组特征鉴别及变化规律研究

寄生于人体微生物基因多样性远大于人类本身的基因组，其组成随宿主的居住环境、年龄、饮食、机体生理状态不同而改变，肠道微生物影响着宿主的代谢和生理过程。体内微生物种类的改变与多种疾病如肥胖、糖尿病和消化道疾病等相关，但其机理不明确。久居高原环境人群及其体内微生物具有其特殊性。随着西部开发政策的推行，大量高原人群到内地工作、学习，他们在适应平原环境过程中，随着环境、饮食结构等改变，体内微生物群落可能会发生改变。了解这些多样性改变，对深入研究高原人群适应、脱适应和相关疾病具有重大意义。本研究随机抽取居住于高原的汉族和藏族正常人各200例，采集口腔和肠道排泄物样本，进行宏基因组研究并与表型进行关联分析。采用二代测序技术对不同民族群体、不同海拔、不同饮食结构和不同时间段的消化道菌群多样性组成进行详尽分析，建立中国高原人群特有消化道菌群数据库，并试图寻找该人群与适应和脱适应相关的特异菌群。

The genetic diversity of the microbial community populating in human body is greater than their hosts' karyome, and their compositions change with hosts' living environment, age, diet and physiological state. Intestinal microbial affects hosts' metabolism and physiological processes. The changes of microbial species in vivo are associated with many diseases, such as obesity, diabetes, liver and gastrointestinal diseases. But its mechanism is unclear. People and symbiotic microorganisms living in the plateau have diversities. With the further implementation of the western development policy, lots of people move to the plain from plateau for work and study. During adapting to plain environment, the diversity of microorganisms may be changed following the change of their hosts' environment and diet structures. It is important to study these changes to understand the adaptation, de-adaptation and plateau related diseases. In this study, 400 random samples, including 200 Han and 200 Zang ethnic population lived in Tibet plateau, will be chosen. We collect their oral and intestinal fecal secretion and study metagenomics by using the ILLUMINA sequencing technology. By analyzing the digestive flora diversity of different ethnic groups in different attitude regions and different diet structures, the gastrointestinal micro-organisms database of highland population will be established and a specific flora and digestive-related microbial groups could be found.