Association Between Selected Vitamin D receptor polymorphisms and gestational diabetes mellitus? A systematic review and meta-analysis

Gestational diabetes mellitus (GDM) is glucose intolerance that occurs during pregnancy and can lead to various pregnancy complications. A common genetic factor proposed to be involved in GDM are polymorphisms in the vitamin D receptor (VDR) gene. Vitamin D binds to the VDR gene and leads to the transcription of other genes. Mutations in the VDR gene will impact the effect of vitamin D on the receptor. Vitamin D is involved in the implantation, differentiation, and growth of foetal cells and VDR polymorphisms have been associated with the occurrence of GDM, but findings are contradictory. We assessed the relationship between GDM and VDR polymorphisms. This systematic review and meta-analysis based on the association between VDR polymorphisms and GDM, retrieved from PubMed central, Medline, Google Scholar, EBSCOhost, LILACS, Cochrane Library, ScienceDirect, and Web of Science Core Collection databases. The eligibility of studies was assessed by the two independent reviewers with third reviewer serving as arbitrator following specific criteria. data was analysed with the Review Manager (RevMan) 5.3 software. This systematic review and meta-analysis revealed no statistical difference between GDM and control group for rs7975232, rs10735810, and rs731236 [OR = 1.08 (0.91, 1.28); p = 0.36], [OR= 0.81 (0.57,1.14); p = 0.22], and [OR=1.80 (1.31, 2.46) p= 0.0002] respectively. VDR gene polymorphisms rs7975232, rs10735810 and rs731236 are not associated with gestational diabetes mellitus. The rs731236 has protective effects against GDM, whereas rs10735810 increases susceptibility to GDM. Further studies with lager sample size especially in low middle income countries are needed to confirm these findings.