Pathogenic CSNK2B (MIM: 115441) variants have been reported to co-segregate with global developmental delay and epilepsy, a condition termed Poirier-Bienvenu neurodevelopmental syndrome (POBINDS; MIM: 618732).6, 7, 8 Experiments on the functional consequences of the CSNK2B variants were not presented in any of these reports. This evidence concerns the gene CSNK2B and Global developmental delay.