5q14.3 neurocutaneous syndrome: a novel continguous gene syndrome caused by simultaneous deletion of RASA1 and MEF2C.

Overview

Haploinsufficiency of RASA1, located on chromosome 5q14.3, has been identified as the etiology underlying the disorder capillary malformation-arteriovenous malformation (CM-AVM). Recently, haploinsufficiency of MEF2C, located 1.33 Mb distal to RASA1 on chromosome 5q14.3, has been implicated as the genetic etiology underlying a complex array of deficits including mental retardation, hypotonia, absent speech, seizures, and brain anomalies. Here we report a patient who is haploinsufficient in both RASA1 and MEF2C who presents with dermatologic and neurologic abnormalities that constitute a 5q14.3 neurocutaneous syndrome. This finding highlights the need to assess for CM-AVM in patients with neurologic features consistent with MEF2C haploinsufficiency, and vice versa.