Le Dr Frank Bellivier fait le point des connaissances sur la génétique des maladies psychiatriques.
Mot(s) clés libre(s) : génétique, neuroscience, psychiatrie, schizophrénie

Bipolar disorders and schizophrenia continue to present complex diagnostic and therapeutic challenges. Traditionally, bipolar disorder has been considered as a clinical entity distinct from schizophrenia, although that assumption is being increasingly challenged. Despite the availability of international classifications, such as the DSM-IV and ICD-10, which clearly distinguish these two disorders, diagnosis is still problematic due to instability and symptoms overlap. In addition, each disorder is heterogeneous characterized by different subtypes and degrees of severity. Proponents of a bipolar continuum theory support the concept of an expanded psychiatric continuum ranging from bipolar disorders to schizophrenia. Although, the concept of continuum has never been clearly defined, this notion is supported by various independent findings. Both bipolar disorder and schizophrenia demonstrate a high degree of genetic heritability. Some data reported in family and twin studies suggest a genetic overlap between the two disorders. Gene mapping for both diseases is in its early stages, but certain susceptibility markers appear to be located on the same chromosomes and some candidate genes have been associated with each of these disorders. Bipolar disorder and schizophrenia also demonstrate some similarities in neurotransmitter dysfunction. Neuroimaging and cognitive studies have also provided arguments suggesting the existence of a continuum between schizophrenia and bipolar disorder. As further indirect evidence of a possible association, many atypical antipsychotic agents approved for the treatment of schizophrenia are also proving useful for bipolar disorder. Conversely, mood stabilizers have also been proposed in the treatment of schizophrenia. Recent research using dimensional and genetic approaches may reconcile both (unitary versus Kraepelinian) conceptions. Origine SPI-EAO CERIMES Canal-U Santé et Sport Générique Auteurs : Frank BELLIVIER – Franck Schurhoff Pôle de Psychiatrie CHU Mondor-Chenevier Créteil /INSERM U842 Paris XII
Mot(s) clés libre(s) : Collège de France, gènes, neurobiologie, psychiatrie, schizophrénie, troubles bipolaire