Genome-Wide DNA Methylation Changes in Placenta Tissues Associated with Small or Gestational age Newborns; Cohort Study In The Chinese Population

Aim: To investigate DNA methylation changes in placenta tissues associated with small for gestational age (SGA). Materials & methods: A prospective cohort study consisting of 1292 pregnant women from China (including 39 SGA with placenta tissues) was performed, microarray and pyrosequencing were conducted. Results: Total 2012 methylation variable positions stood out from all probes (p < 0.05; Δβ > 0.2). In SGA cases, a CpG site within ANKRD20B showed lower methylation level (p = 0.032) than appropriate for gestational age in validation cohort. Five sites within FAM198A (p = 0.047, 0.050, 0.039, 0.026 and 0.043, respectively) had a reduced methylation in male newborns whose mother had preconception folic acid supplementation. Conclusion: DNA methylation changes in placenta tissues may be associated with SGA, maternal preconception folic acid supplementation status and also be fetal sex-specific.