Relationship between FcγRIIB gene polymorphisms, periodontitis and adverse pregnancy outcomes in pregnant women

Background: FcγRIIb acts as a negative feedback regulator by inhibiting B-cell antigen receptor-elicited activation signals through tyrosine phosphorylation of immunoreceptor tyrosine-based inhibitory motif (ITIM). FcγRIIb gene polymorphisms might be related to the lower level of IgG antibody response to periodontal bacteria and lead to the development of periodontitis. Our previous studies showed that there was significant association between FcγRIIb gene polymorphisms in pregnant women and adverse pregnancy outcomes, such as preeclampsia or preterm birth with low birth weight. Periodontitis as a risk factor for adverse pregnancy outcomes has been widely and generally reported, and many studies found inflammation might lead to the development of adverse pregnancy outcomes. Review: We assume the development of adverse pregnancy outcomes may be attributed in part to inflammation such as periodontitis enhanced by FcγRIIb gene polymorphisms. Although significant associations between clinical periodontal parameters and adverse pregnancy outcomes have not been found, subgingival levels of periodontal bacteria were associated with adverse pregnancy outcomes in our study. Therefore, we will summary and discuss previous studies about associations between FcγRIIb gene polymorphisms, periodontitis and adverse pregnancy outcomes, as well as the biological mechanism between them in this review.