Prenatal diagnosis of Miller–Dieker syndrome by chromosomal microarray

Abstract Objective To assess the experience on prenatal diagnosis of Miller–Dieker syndrome (MDS) to further delineate the fetal presentation of this syndrome. Methods This was a retrospective study. Fetal MDS was diagnosed prenatally by chromosomal microarray (CMA). Clinical data were reviewed for these cases, including maternal characteristics, indications for prenatal diagnosis, sonographic findings, CMA results, and pregnancy outcomes. Results Four cases were diagnosis as MDS by CMA. The most common sonographic features were ventriculomegaly (3/4) and polyhydramnios (2/4). Deletion sizes ranged from 1.5 to 5.4 Mb. All microdeletions were located at the MDS critical region and showed haploinsufficiency of the YWHAE, CRK, and PAFAH1B1. All patients chose to terminate the pregnancy. Parental chromosome analysis were preformed in three cases and demonstrated that two cases were de novo and one case was caused by inherited derivative chromosomes from parental balanced translocations. Conclusion The most common prenatal ultrasound findings of MDS were ventriculomegaly and polyhydramnios. CMA can improve diagnostic precision for detecting MDS.