Deletion of 15q26.1 region with absence epilepsy respond to valproic acid: A Literature Overview and A Case Report from Qatar

Abstract

Chromosomal abnormalities involving deletions and duplications are known to cause severe developmental disorders, including mental retardation, dysmorphism, and seizures, in children. As the technique of array-based comparative genomic hybridization is being applied more frequently in the diagnostic evaluation of children with developmental disorders; novel pathologic chromosomal abnormalities are being identified in relation to various type of epilepsies in childhood. We report the case of a 4-year-old girl with a history of speech delay and communication disorder, mild dysmorphic features, and absence epilepsy with a de novo microdeletion 15q26.1. A much larger (5 Mb) but overlapping microdeletion has been previously reported in similar several cases with similar phenotype including intractable myoclonic and absence epilepsy, growth delay, and dysmorphic features. This leads us to propose that a potential candidate gene or genes within the deleted region involved in the pathogenesis of some forms of generalized intractable epilepsy, previously considered idiopathic should consider genetic study for childhood epilepsies especially if it was associated with underlying developmental delay in any particular aspect as speech delay in our case.