Fibroblast growth factor receptor 2 () gene encodes a protein of the fibroblast growth factor receptor family.gene expression is associated with the regulation of implantation process of placenta which plays a vital role in fetal growth. DNA methylation is widely known as a mechanism of fetal growth. However, it is unclear whether and how DNA methylation ofgene in the placenta is associated with full-term low birth weight. This case-control study aims to explore the links betweenmethylation in placenta and full-term low birth weight and to further examine the mediation effect of placental surface area on this association.
We conducted analyses for each of the five valid CpG sites atin 165 mother-baby pairs (86 FT-LBW vs. 79 FT-NBW) and found that per one standard deviation increase in the DNA methylation of CpG 11 atwas associated with 1.64-fold higher risk of full-term low birth weight (OR = 1.64, 95% CI = [1.07, 2.52]) and 0.18 standard deviation decrease in placental surface area ( = - 0.18; standard error = 0.08, = 0.02). The mediation effect of placental surface area on the association between DNA methylation and full-term low birth weight was significant in girls (OR = 1.38, 95% CI = [1.05, 1.80]) but not in boys. The estimated mediation proportion was 48.38%.
Our findings suggested that placental surface area mediated the association between DNA methylation ofin placenta and full-term low birth weight in a sex-specific manner. Our study supported the importance of placental epigenetic changes in placental development and fetal growth.