Etiological Diagnosis and Disease Course of Birk–Barel Syndrome in an Adult Woman with a KCNK9 Variant

A pathogenic heterozygous missense variant in the <i>KCNK9</i> gene corresponding with a diagnosis of Birk-Barel syndrome was considered to be largely responsible for the severely disinhibited behaviours and causative for the absence epilepsy. For adequate diagnosis and treatment of neurodevelopmental disorders, this case clearly demonstrates the importance of adherence to clinical standards, in particular periodically renewed genetic analysis by means of WES/WGS.