Last modified: 2018-09-09
Abstract
INTRODUCTION
MEF2C gene (Myocyte enhancer factor 2) has a crucial function in the homeostatic control of activity-dependent synaptogenesis that plays a role in the establishment of functional neuronal circuits during development and memory storage. Specifically, MEF2C haploinsufficiency in humans seems to impair central nervous system function. Clinically, the syndrome is characterized by severe intellectual disability, absence of speech and limited walking abilities, hypotonia, epilepsy, stereotypic movements, minor brain malformations and dysmorphic features.
AIM
To report 3 patients with clinical features associated with MEF2C mutation.
RESULTS
We describe 3 patients (2 women and 1 men) 4 years and 19 months respectively, who presented to our clinic with developmental delay, hypotonia, stereotypic movements and epilepsy. Both girls had minimal dysmorphc features and started at the age of 4 months with fever induced seizures. The boy presented with epileptic spasms. Two of them developed an epileptic encephalopathy. On MRI sequences, we found corpus callosal hypoplasia and perysilvian atrophy. Neurometabolic and karyotype studies were normal. Molecular analysis revealed a MEF2C mutation which includes a duplication/traslocation in 2 patients and a microdeletion in the third.
CONCLUSION
Severe intellectual disability with inability to speak and epilepsy are universal features in patients with MEF2C mutations. Although MEF2C haploinsufficiency prevalence is yet to be determined, it should be considered in the differential diagnosis of patients with severe intellectual disability and Rett-like features.