MicroRNA-155 rs767649 polymorphism is associated with susceptibility to peri-implantitis.

Objective: To examine how the miR-155 rs767649 polymorphism affects miR-155 expression and to investigate its association with peri-implantitis susceptibility.

Design: One hundred and eighty-seven peri-implantitis patients and 196 healthy implant subjects were enrolled. The expression level of miR-155 in the subjects' serum was tested using qRT-PCR. The rs767649 polymorphism was genotyped with the TaqMan SNP genotyping assay. The genotype and allele distributions of miR-155 rs767649 polymorphism were compared between the case and control groups. Target genes of miR-155 were predicted using four online databases (ENCORI, miRDB, miRWalk and TargetScan). Functions and pathways of these target genes were annotated through GO and KEGG enrichment.

Results: The qRT-PCR results revealed that miR-155 was upregulated in patients with peri-implantitis (P < 0.001) based on Student's t test analysis. Carriers of the rs767649 TT genotype had higher levels of miR-155 expression in their serum (P < 0.001) and a greater risk of peri-implantitis compared to those with the TA/AA genotype according to the chi-square test results (P = 0.016). The downstream target genes of miR-155 may be involved in pathways such as Kaposi sarcoma-associated herpesvirus infection, ubiquitin-protein hydrolysis, and cell differentiation.

Conclusion: The results revealed a correlation between the miR-155 rs767649 polymorphism and susceptibility to peri-implantitis. The rs767649 TT genotype upregulates miR-155 expression, which regulates downstream signaling pathways and increases the chance of peri-implantitis.