c-Jun N-terminal kinase (JNK) signaling plays a key role in synaptic plasticity and neuronal communication.1 In humans, mutations in JNK genes lead to intellectual disability.2 We have identified a common variant in the MAP2K7 gene (encoding MAP kinase kinase 7 (MAP2K7), which activates JNKs) that shows a strong association with schizophrenia (ScZ).3 Genes in this signaling pathway are independently associated with ScZ (supplementary figure S1).4,5 Hence, strong evidence implicates the pathways modulated by MAP2K7 in ScZ. This evidence concerns the gene MAPK8 and Intellectual disability.