The Val158Met polymorphism of the gene encoding catechol-O-methyltransferase (COMT) is one of the most widely tested variants for association with psychiatric disorders, but replication has been inconsistent including both sex limitation and heterogeneity of the associated allele.
A variation in catechol-O-methyltransferase (COMT) gene (Val(108/158)Met) affects the physiological response of hippocampal-prefrontal circuits, predicts variation in human memory and is associated with increased risk for psychiatric disorders.
Catechol-O-methyltransferase (COMT): a gene contributing to sex differences in brain function, and to sexual dimorphism in the predisposition to psychiatric disorders.
Future longitudinal studies focusing on additional COMT polymorphic sites and other candidate genes from the deleted region will elucidate the molecular pathways leading to schizophrenia and other psychiatric disorders in VCFS.
The COMT gene is located on chromosome 22q11, a region strongly implicated in the aetiology of several psychiatric disorders, in particular schizophrenia.
The identification of candidate genes for heart anomalies, mental illness, and other clinical phenotypes has been reported in the past year with a focus on TBX1 for cardiac and craniofacial phenotypes and COMT and PRODH for psychiatric disorders.
The involvement of the COMT gene in the metabolic pathway of these neurotransmitters has made it an attractive candidate gene for many psychiatric disorders.
One hundred eighty-one AD patients and 208 age-matched controls underwent clinical and neuropsychological examination, behavioural and psychiatric disturbances evaluation, and ApoE and COMT genotyping.
Of special interest is the role of this gene in major psychoses especially since a microdeletion (22q11) containing the COMT gene (velo-cardio-facial syndrome) also carries with it several types of behavioral disorders, including an increased prevalence of schizophrenia.
We then examined genetic polymorphisms in four candidate genes (DRD4, DAT, COMT and MAOA) that have been shown to contribute to the risk of developing various psychiatric disorders where attention is disrupted.
Further studies are required to better understand the association of symptomatology of schizophrenia and other psychiatric disorders with COMT gene polymorphism.
A common functional polymorphism that results in a three- to four-fold difference in catechol-O-methyltransferase (COMT) enzyme activity has been related to psychiatric disorders such as ultra-ultra rapid cycling bipolar disorder, drug abuse and alcoholism (Lachman et al., 1996a; Karayiorgou et al., 1997; Vandenbergh et al., 1997; Papolos et al., 1998; Tiihonen et al., 1999).
Catechol-O-methyltransferase (COMT) is one of the major mammalian enzymes involved in the metabolic degradation of catecholamines and is considered a candidate for several psychiatric disorders and symptoms, including the psychopathology associated with the 22q11 microdeletion syndrome.
High COMT activity in women with depression is apparent mainly in patients whose first and second degree relatives revealed psychiatric disturbances, particularly affective disorders.