Endophenotype strategies for the study of neuropsychiatric disorders

The identification of genes that contribute to a susceptibility to complex neuropsychiatric disorders such as schizophrenia, major depression and bipolar disorders has been not very successful using conventional genetic approach. There are several problems associating with this conventional approach including carriers of genes cannot be identified in the absence of manifest symptoms and the heterogeneity of neuropsychiatric disorders. A new direction that appears encouraging is the identification of neurobiological or neurobehavioural characteristics associated with these complex neuropsychiatric disorders, or endophenotypes, that may be more closely linked to gene expression. Endophenotype is a biomarker associating with genetic components as well as the clinical symptoms of neuropsychiatric disorders. It plays an important role to bridge the gap between microscopic level and macroscopic level of neuropsychiatric disorders. The identification of endophenotype, along with the advanced genetic analysis such genomewise association studies, is very crucial to the identification of genes that predispose someone to neuropsychiatric disorders. Therefore, the study of endophenotype is of particular useful for us to understand the underlying mechanism of the illness process of neuropsychiatric disorders, aiding the clinicians to make accurate diagnosis and for early detection purposes.

With the supported from the National Basic Research Programme of China (973 Progamme) (2007CB512302), The Key Laboratory of Mental Health of the Institute of Psychology, Chinese Academy of Sciences has organized a strategic symposium for endophenotypes, titled ""Endophenotype strategy for psychotic disorders and summit meeting of Key Laboratory of Mental Health, Institute of Psychology, CAS". International renowned scholars of this field presented their updated findings on endophenotypes. Professor Irving Gottesman, the founder of the endophenotype for neuropsychiatric disorders, was also giving a video lecture to all the participants. Their work was published in the special issue of Chinese Science Bulletin, 2011, Vol. 56(32).

Cognitive deficits have been widely recognized as core features of schizophrenia, and as major contributors to the clinical outcome of the disorder.

They are also studied widely as 'endophenotypes', reflecting a growing consensus that schizophrenia is a broader, more multidimensional illness than the diagnostic criteria required for its formal diagnosis. Stone and Hsi adopted this evolving view of cognition underlying its utilization in recent initiatives for intervention and assessment in schizophrenia, and illustrated it with the use of the MATRICS Cognitive Consensus Battery, a standardized battery of neuropsychological tests developed to assess the effectiveness of cognitive enhancing treatments in schizophrenia. They then further provided evidence to show the utilization of neuropsychological deficits in the identification, validation and remediation of a liability syndrome for schizophrenia ('schizotaxia'). Taken together, the inclusion of cognition in broader consortium and other collaborative efforts to assess interrelationships across multiple dimensions of function will provide important catalysts for progress in each individual dimension. Utilization of cognition underscores its functional importance in the clinical outcome of schizophrenia. Moreover, it helps to illuminate indicators of liability for schizophrenia that might be amenable to remediation.