A new patient with Andermann syndrome: an underdiagnosed clinical genetics entity?: Andermann syndrome is an autosomal recessive disorder characterized by the agenesis of the corpus callosum and peripheral neuropathy (ACCPN). People affected by Andermann syndrome have mental retardation, areflexia and severe progressive neuropathy often accompanied by psychiatric symptoms, and they typically die in the third decade of their life. We here report the case of a 5 year-old Turkish boy born to consanguineous parents. He presented to clinical attention with delayed development and epilepsy and was found to have dysmorphic characteristics, areflexia and severe neuropathy on exam. Imaging studies were remarkable for agenesis of corpus callosum. SLC12A6 screening revealed the presence of R1011X mutation; potentially responsible for the changes in intracellular and extracellular ion concentrations, leading to defects in cortical electrical activity.