BRAF and familial atrioventricular septal defect: Moreover, while our data shows that miR-15a-5p may have a central role in ECD, the study has several limitations: First, the cell-line models were not purified from ECD patients, however, we believe that the model we have chosen is the closest one to ECD because it is generated from myeloid progenitors, it harbor mutations in the MAPK signaling pathway, specifically in BRAF and RAS, which are common mutations found in ECD patients, and it expresses low levels of miR-15a-5p, as seen in ECD plasma and tissue samples.