Clinical diversity of different genetic variants changes the way we look at diseases; Two cases of ACTL6B gene-related DECAM syndrome

Abstract

Developmental Delay, Epileptic Encephalopathy, Cerebral Atrophy, and Abnormal Myelination syndrome (DECAM syndrome) is a rare autosomal recessive neurodevelopmental disorder with developmental delay, epileptic encephalopathy, cerebral atrophy, severe intellectual disability, and autistic features. It is also called Developmental and Epileptic Encephalopathy 76 (DEE76). In this report, we present two cases of DECAM syndrome, a 5-year-old boy and a 9-year-old girl, who presented with refractory seizures, microcephaly and severe developmental delay. Although both patients had homozygous mutation in the ACTL6B gene, the time of onset and clinical severity of the disease were different. We attributed this to the mutations being in different regions and aimed to emphasize the importance of genotype-phenotype correlation.