Dilated cardiomyopathy in a patient with autosomal dominant EEF1A2-related neurodevelopmental disorder.

The EEF1A2 gene encodes eukaryotic translation elongation factor 1α2, an integral component of the elongation factor complex. Heterozygous pathogenic variants in EEF1A2 are associated with neurodevelopmental disorders characterized by epilepsy, global developmental delay, and autism. To date, dilated cardiomyopathy has only been reported in two siblings with neurodevelopmental phenotypes and a homozygous missense variant in EEF1A2. This report describes a nine-year-old female patient who presented with neurodevelopmental phenotypes and dilated cardiomyopathy. Analysis of 193 epilepsy genes by focused exome sequencing revealed a novel heterozygous variant c.46G > C (p.Val16Leu; NM_001958.3) in EEF1A2. The variant was not detected in either parent, confirming its de novo origin. No additional variants that explain the patient's phenotypes were found by subsequent whole exome analysis. Copy number analysis of the exome data and exon-level microarray excluded a deletion in the other allele of EEF1A2. We present the first patient with a heterozygous pathogenic EEF1A2 variant who had dilated cardiomyopathy as well as neurodevelopmental phenotypes, suggesting that this cardiac phenotype may be associated with the autosomal dominant form of the EEF1A2-related disorder.