microRNAs in the blastocoel fluid as accessible indicators of chromosomal normality

MicroRNAs (miRNAs) derived from the pre-implantation blastocoel fluid (BF) have attracted interest as accessible biomarkers indicative of embryonic health in ongoing IVF cycles. Therefore, we investigated expression levels of some aneuploidy-associated miRNAs and implantation-related mRNAs as predictive markers for embryo chromosomal normality. In this study, the BF of 25 blastocysts that had been checked for aneuploidy (aneuploid=17 and euploid=8) was aspirated and the expression of 10 miRNAs (miR-20a, miR-30c, miR-661, miR-372, miR-142, miR-191, miR-345, miR-339, miR-141, and miR-27b) and four genes (ERBB4, SELL, ITGB3, ITGAV) were evaluated using real time-PCR. Results showed that the levels of miR-661 and miR-20a were significantly higher in the BF of the aneuploid embryos compared to the euploid group (p = 0.0017 and 0.004, respectively). A comparison of the mRNA levels between the aneuploid and euploid groups also demonstrated a significant difference in ITGAV (p = 0.013) and SELL (p = 0.0317) levels. In the euploid group, a negative correlation was found between ITGB3 and miR-30c (r = -0.71, p = 0.08), and in the aneuploid group, a positive correlation was found between ERBB4 and miR-345 (r = 0.71, p = 0.02). It can be suggested that miR-20a, miR-661, and ITGAV levels of BF could be used as less-invasive biomarkers to evaluate embryonic health. Moreover, aneuploidy-related miRNA levels were associated with levels of genes involved in embryo implantation.