Maternal and fetal capillary malformation-arteriovenous malformation (CM-AVM) due to a novel RASA1 mutation presenting with prenatal non-immune hydrops fetalis.

RASA1 mutations have been shown to cause capillary malformation-arteriovenous malformation (CM-AVM). We describe a patient with CM-AVM and a fetus who presented with non-immune hydrops fetalis during the pregnancy. Sequencing revealed a novel RASA1 mutation in the RASGAP domain that results in a loss of function of p120-RasGap. This report expands our current genetic and clinical understanding of CM-AVM in pregnancy.