Twelve of the down-regulated transcripts are schizophrenia-related with regulation of 10 by both Apoer2-ICDs (ARHGAP18, GSTM1, HAGH, HDAC1, HTR1F, JAG1, NDEL1, NGFR, S100B, TRPM1) and 2 with only the Apoer2-ICD[Δ19] (RASD2, SMAD5). The gene discussed is ARHGAP18; the disease is schizophrenia.