Autism spectrum disorders and schizophrenia are two distinct diseases according to DSM-IV (1) and ICD-10 (2). However, studies have shown that these two disorders share a number of phenotypic features, including impairments in social cognition (55) and theory of mind (56,57). There is also evidence that adult ASDs who are relatively high functioning and verbal are more likely to present schizophrenic features, especially of the disorganized subtype (58). In addition, recent studies have reported common genes that are involved in both ASD and schizophrenia, for example, association of gene DISC1 (disrupted in schizophrenia 1) (59) and copy number variations in gene NRXN1 (neurexin 1) (60). The overlap of the clinical features and genes indicate that shared common pathogenic mechanisms may contribute to the liability for both ASD and schizophrenia. If our finding at this locus is replicated, further study will be needed to determine if the linkage evidence in this region for high-functioning ASD and for schizophrenia reflects the same biological pathways for some common intermediate phenotype(s) between these two diseases or if there is a different locus underlying each disorder within this region.
