The Effect of an Obesogenic Maternal Environment on Expression of Fetal Umbilical Cord Blood miRNA.

OBJECTIVE

Exposure to maternal obesity in utero predisposes offspring to obesity and metabolic disease. This study investigated whether maternal obesity is associated with alterations in expression of fetal microRNA (miRNA).

STUDY DESIGN

A cohort study of women with body mass index (BMI) ≥35 kg/m(2) (n = 16) versus those with normal BMI 20 to 24.9 (n = 20) was performed. All participants had normal glucose tolerance (1-hour glucose challenge test <130) and normally grown neonates (2700-3500 g). Umbilical cord samples were collected immediately after delivery. Expression of miRNA was assessed using Affymetrix GeneChip miRNA 3.0 Arrays. Differential miRNA expression was determined using Student t tests with Benjamini-Hocherg correction.

RESULTS

For 1733 human mature miRNAs, the expression levels were not statistically different in umbilical cord blood samples from pregnancies of obese women compared to controls.

CONCLUSION

Expression of fetal miRNA is not altered in umbilical cord blood in response to in utero exposure to obesity. Alternate mechanisms underlying the fetal effects of maternal obesity should be explored.