LAUSR

BACKGROUND Studies have found that HIV is mainly transmitted through the mucosal surface, and the entrance of early progression of the disease is the rectal and colonic mucosa. So, this paper aimed to explore and analyze the structural differences of gut microbiome between men who have sex with men (MSM) and those who haven't sex with men (Non-MSM), expecting finding novel biological factors that potentially impact transmission and/or disease in MSM population. METHODS We collected a total of 33 stool samples, 16 were MSM and 17 were Non-MSM. The 16S rRNA gene amplification sequencing was used to detect the alteration and structure of the gut microbiome community in two groups. RESULTS The difference in β diversity of gut microbiome of two groups of subjects was statistically significant (P<0.001), indicating that the difference in the structure of the gut microbiome of two groups was statistically significant. Compared with the phylum and genus level of Non-MSM group, the relative abundances of Actinobacteria, Proteobacteria, genera Collinsella, Prevotella, Bifidobacterium and Ralstonia in MSM group were higher (P<0.001, P<0.05, LDA score(log10)>2), and the relative abundance of Bacteroidetes, genera Erysipelotrichaceae incertae sedis, Bilophila, Holdemania, Clostridium XIVb and Bacteroidaceae in MSM group was lower (P<0.01, LDA score(log10)>2). CONCLUSIONS There are some differences in the structure of gut microbiome between MSM group and Non-MSM group. It indicates the differences in behavior and characteristics between MSM and Non-MSM population may be related to the difference in the structure of gut microbiome.