Abstract
Genes are major contributors to schizophrenia. Studies aiming to identify susceptibility genes for schizophrenia are faced with the confounds of subjective clinical criteria, commonly occurring phenocopies, significant between-subject variability of candidate traits, and the likelihood of allelic and locus heterogeneity. The intermediate phenotype concept represents a strategy for identifying risk genes for schizophrenia and for characterizing the neural systems affected by risk gene variants to elucidate quantitative, mechanistic aspects of brain function implicated in schizophrenia. Intermediate phenotypes are defined by being heritable, being able to measure quantitatively ; being related to the disorder and its symptoms in the general population ; being stable over time ; showing increased expression in unaffected relatives of probands ; and cosegregation with the disorder in families. Intermediate phenotypes in schizophrenia are neurocognition, neuroimaging, neurophysiology, etc. Progress in the identification of meaningful intermediate phenotypes in schizophrenia has been made by the advance of newer methods in cognitive neuroscience and neuroimaging, and the use of combined multimodal techniques. In this review, we present concept, recent work, and future perspective of intermediate phenotype.
