Expression profile of maternal circulating microRNAs as non-invasive biomarkers for prenatal diagnosis of congenital heart defects

Objective: The discovery of cell free fetal microRNAs (miRNAs) in maternal circulation has opened up novel probabilities for non-invasive prenatal diagnosis. This study aims to investigate circulating miRNAs as potential biomarkers in the serum of pregnant women with congenital heart defect (CHD) fetuses. Method: A total of 110 pregnant women including 50 CHD cases and 60 healthy controls were included in this study. miRNA microarray followed by real-time PCR was used to explore miRNA expression. Receiver operating characteristic (ROC) curves were calculated to assess the diagnostic capability of miRNAs for fetal CHDs. Results: 38 Serum miRNAs were revealed to be differentially expressed in the CHD group as compared to control group via microarray. Among these, nine down-regulated and three up-regulated miRNAs were validated by real-time PCR. Ten of these miRNAs were rapidly reduced in the normal maternal serum after delivery as compared to before delivery. In particular, we identified a biomarker panel consisting of four miRNAs (miR-142-5p, miR-1275, miR-4666a-3p and miR-3664-3p) capable of distinguishing CHDs from controls (area under the ROC curve (AUC), 0.920; p < 0.0001). Conclusion: The discovery of these dysregulated pregnancy-associated miRNAs in maternal serum may be potential biomarkers for non-invasive prenatal diagnosis of fetal CHDs.