Brain Abnormalities in Prenatally Diagnosed Rubinstein-Taybi Syndrome

Rubinstein-Taybi syndrome (RSTS; OMIM 180849) is a rare autosomal dominant disorder characterized by craniofacial dysmorphism, broad halluces and thumbs, variable structural abnormalities and intellectual disability. It is caused by a pathogenic variant in the CREBBP or EP300 genes. Although distinctive features are described, prenatal diagnosis is rare. We report five prenatally diagnosed cases of RSTS, all with brain abnormalities. On neurosonography, corpus callosum abnormalities were found in 3/5 cases. The remaining two cases had abnormal posterior fossas, one with vermian hypoplasia and the other with Dandy-Walker malformation (DWM). A CREBBP gene mutation was identified in all cases-two on microarray (CMA) and three on Trio-whole-exome-sequencing (Trio-WES). This report will allow for a better understanding of the fetal brain findings associated with RSTS.