Differentially Expressed MicroRNAs in Maternal Plasma for the Noninvasive Prenatal Diagnosis of Down Syndrome (Trisomy 21)

Abstract

Objectives. Most developmental processes are under the control of small regulatory RNAs called microRNAs (miRNAs). We hypothesize that different fetal developmental processes might be reflected by extracellular miRNAs in maternal plasma and may be utilized as biomarkers for the noninvasive prenatal diagnosis of chromosomal aneuploidies. In this proof-of-concept study, we report on the identification of extracellular miRNAs in maternal plasma of Down syndrome (DS) pregnancies. Methods. Using high-throughput quantitative PCR (HT-qPCR), 1043 miRNAs were investigated in maternal plasma via comparison of seven DS pregnancies with age and fetal sex matched controls. Results. Six hundred and ninety-five miRNAs were identified. Thirty-six significantly differentially expressed mature miRNAs were identified as potential biomarkers. Hierarchical cluster analysis of these miRNAs resulted in the clear discrimination of DS from euploid pregnancies. Gene targets of the differentially expressed miRNAs were enriched in signaling pathways such as mucin type-O-glycans, ECM-receptor interactions, TGF-beta, and endocytosis, which have been previously associated with DS. Conclusions. miRNAs are promising and stable biomarkers for a broad range of diseases and may allow a reliable, cost-efficient diagnostic tool for the noninvasive prenatal diagnosis of DS.

DEGUM, ÖGUM, SGUM and FMF Germany Recommendations for the Implementation of First-Trimester Screening, Detailed Ultrasound, Cell-Free DNA Screening and Diagnostic Procedures

“…Methods for isolating individual fetal cells [188,189] or examining microRNA [190,191] as well as the isolation of trophoblast cells from cervical smears [187,192] or from embryonic cells after coelocentesis [193] have been described in small study series. Faster and cheaper sequencing techniques could provide new diagnostic possibilities even in the case of small cell numbers or fragments.…”

Genome-wide miRNA profiling in plasma of pregnant women with Down syndrome fetuses

“…However, placenta is not the only determinant of pregnancy-associated miRNA levels in maternal and fetal blood, another source or mechanism influencing these levels is probably involved [29]. Hypothesis that miRNAs are somehow transported from fetus into the maternal circulation and vice versa is still unproven [26].…”

“…3) four miRNAs which did not fulfil the above conditions but were reported in the literature as being possibly associated with Down syndrome pathophysiology [26,30,31].…”

“…They compared 33 euploid and 23 trisomic pregnancies and found two miRNAs -miR-99a and miR-3156, which were elevated in DS pregnancies. The most comprehensive study so far has been carried out by Kamhieh-Milz et al [26]. A group of 1043 miRNAs were analyzed using high-throughput qPCR SmartChip Human miRNA Panel, nevertheless, a very small number of samples were included (7 DS fetuses; 7 controls).…”

Prenatal profile of Pallister‐Killian syndrome: Retrospective analysis of 114 pregnancies, literature review and approach to prenatal diagnosis

“…As the percentage of mosaicism does not correlate with the severity of congenital anomalies in PKS fetuses (Libotte et al ) other markers of severity and poor outcomes would be helpful. Recently, abnormal extracellular microRNAs (miRNAs) in maternal plasma have been showed early in Down syndrome pregnancies and in those pregnancies complicated by gestational diabetes, preeclampsia, fetal growth restriction (Chiofalo et al ; Kamhieh‐Milz et al ; Lagana’ et al ; Sebastiani et al ). As five miRNAs located on 12p have already been reported to be overexpressed in skin fibroblasts from PKS patients, further studies on maternal plasma miRNAs profile in PKS pregnancies might open a window to identify new potential diagnostic and prognostic biomarkers (Izumi et al ).…”