Due to the different rates of diabetes in different ethnic groups and the structural differences in intestinal microbiota, this study evaluated the changes in diabetes-related intestinal microbiota in two ethnic groups. Fifty-six stool samples were collected from subjects from the Han and Mongolian ethnic groups in China, including participants without diabetes (non-diabetic, ND) and with type 2 diabetes (T2D). The 16S rDNA gene V3 + V4 area was extracted from microbiota, amplified by PCR, and used to perform high-throughput sequencing and screen differential microbiota associated with ethnicity. The results showed that there were 44 T2D-related bacterial markers in the Han subjects, of which Flavonifractor, Alistipes, Prevotella, Oscillibacter, Clostridium XlVa, and Lachnospiracea_incertae_sedis were most closely related to diabetes. There were 20 T2D-related bacterial markers in the Mongolian subjects, of which Fastidiosipila and Barnesiella were most closely related to diabetes. The common markers of T2D bacteria in the two ethnic groups were Papillibacter and Bifidobacterium. There were 17 metabolic pathways with significant differences between the ND and T2D groups in the Han group, and 29 metabolic pathways in the Mongolian group. The glutamatergic metabolic pathway was the only common metabolic pathway in two ethnic groups. The composition and function of diabetes-related bacteria were significantly different among the different ethnic groups, which suggested that the influence of ethnic differences should be fully considered when studying the association between diabetes and bacteria. In addition, the common bacterial markers found in diabetic patients of different ethnic groups in this study can be used as potential targets to study the pathogenesis and treatment of diabetes.
Keywords: 16S rDNA; Han; Mongolian; differential microbiota; ethnic group; type 2 diabetes.