PacBio SMRT Sequencing Of The Intestinal Flora Composition In Patients With Gestational Diabetes Mellitus

There is a relatively stable microbial flora in the human intestine,namely the intestinal flora,whose composition is related to the occurrence of various diseases in humans.For example,studies have shown that the dynamic changes of the intestinal flora are closely related to Gestational diabetes mellitus(GDM).Therefore,in this study,we evaluated and compared the intestinal flora in pregnant women according to ethnicity(Mongolian or Han)and GDM status using PacBio SMRT sequencing.Based on PacBio SMRT sequencing technology,this study sequenced and analyzed the full-length 16 S rRNA gene of pregnant women's stool samples.Overall,this study found that the composition of the intestinal flora of pregnant women in the same pregnancy is very similar.In this study,we analyzed the structure of the core flora,and 398 core OTUs were found among the four groups,accounting for 69.3 % of all OTUs.In addition,this study also analyzed the correlation between the core bacteria in different groups at the species level,and found that various microbes exhibited differing degrees of correlation with core flora levels.It shows that the relationship between these core microorganisms is very complex,and this complex network of relationships may play an important role in the dynamic changes of the intestinal flora.In addition,a total of 44 species were identified at the species level in this study.We also found some subtle differences between different groups using statistical analysis software.The relative abundance of Akkermansia muciniphila was significantly higher in the non-GDM pregnant women than in pregnant women with GDM in the Han population,while in Mongolian,the difference between healthy pregnant women and GDM pregnant women was not obvious.In healthy controls,the relative abundance of Bacteroides uniformis in the intestinal flora of Han pregnant women was significantly higher than that in Mongolian pregnant women;however,differences between groups of different ethnic groups were not found in the GDM group.The functional prediction results showed that the functional composition of the four groups of flora was highly similar,and most of the functional genes were related to energy metabolism.There was no significant difference between the GDM patients and controls in the Han population.However,the relative abundance of inorganic ion transport and metabolism([P] Inorganic ion transport and metabolism)was significantly higher in Mongolian GDM patients than in normal Mongolian pregnant women.Therefore,this study infers that during the same pregnancy period,the structure and function of the core intestinal flora of pregnant women during pregnancy are relatively stable,and ethnic differences do not have a significant impact on the flora during pregnancy.However,some low-abundance differential flora can be detected between the four groups,such as Akkermansia muciniphila,whose abundance changes may lead to some changes in the intestinal metabolism related to intestinal nutrient absorption,etc.,and these changes may be closely related to the occurrence of gestational diabetes.The results and ideas of this study will help to elucidate the role of intestinal flora in GDM pathogenesis.