BACKGROUND Impulsivity is a multidimensional construct which has been associated with dopaminergic neurotransmission. Nonetheless, until this moment, few studies addressed the relationship between different types of impulsivity and the single nucleotide polymorphism caused by a substitution of valine (val) with methionine (met) in the 158 codon of the Catechol-o-Methyltransferase gene (COMT-val...

OBJECTIVES Although the Val(158)Met catechol-O-methyltransferase (COMT) gene has been linked with the temperament dimension Novelty Seeking (NS), new insights in this polymorphism might point to a major role for character features as well. Given that individual life experiences may influence Val(158) and Met(158) allele carriers differently it has been suggested that the character trait coopera...

Cytochrome P450 1B1 (CYP1B1) and catechol-O-methyltransferase (COMT) enzymes play critical roles in estrogen metabolism. Alterations in the catalytic activity of CYP1B1 and COMT enzymes have been found associated with altered breast cancer risk in postmenopausal women in many populations. The substitution of leucine (Leu) to valine (Val) at codon 432 increases the catalytic activity of CYP1B1, ...

Cumulative fluoride exposure has adverse influences on children's intelligence quotient (IQ). In addition, catechol-O-methyltransferase (COMT) gene Val158Met polymorphism (rs4680) is associated with cognitive performance. This study aimed to evaluate the associations of COMT polymorphism and alterations of protein profiles with children's intelligence in endemic fluorosis area. We recruited 180...

The objective of this study was to perform a systematic review of the correlations between the single nucleotide polymorphism rs4680 in the catechol-O-methyltransferase (COMT) gene and susceptibility to ovarian cancer. A computer search was carried out for relevant case-control studies published between January 2000 to January 2014 in databases such as Ovid, EBSCO, PubMed, CNKI, CBMDISC, VIP, a...

It has been suggested that symptoms of attention-deficit/hyperactivity disorder (ADHD) is related to low dopamine levels in the prefrontal cortex. The enzyme catechol O-methyltransferase (COMT), which degrades dopamine and other catecholamines, is important for monoamine signaling in this brain-region, but genetic studies of the functional Val158Met (rs4680) polymorphism in ADHD have been incon...

Sleep loss impairs waking functions and is homeostatically compensated in recovery sleep. The mechanisms underlying the consequences of prolonged wakefulness are unknown. The stimulant modafinil may promote primarily dopaminergic neurotransmission. Catechol-O-methyltransferase (COMT) catalyzes the breakdown of cerebral dopamine. A functional Val158Met polymorphism reduces COMT activity, and Val...

The gene encoding catechol-O-methyltransferase (COMT) is a strong candidate for schizophrenia susceptibility, owing to the role of COMT in dopamine metabolism, and the location of the gene within the deleted region in velocardiofacial syndrome, a disorder associated with high rates of schizophrenia. Recently, a highly significant association was reported between schizophrenia and a COMT haploty...

Catechol-O-methyltransferase (COMT) catalyzes the O-methylation of catechol estrogens (CEs), using S-adenosylmethionine (SAM) as a methyl donor. Several studies have indicated that the val108met COMT polymorphism, which results in a 3-4-fold decrease in activity, is associated with increased breast cancer risk. Folate, whose intake levels have also been associated with breast cancer risk, and o...

OBJECTIVE The authors previously reported a relationship between an allele encoding the low activity variant of catechol O-methyltransferase (COMT) and aggressive behavior in schizophrenic patients. This study replicates and extends these findings by using more direct measures of violent behavior. METHOD Fifty-five white patients (34 men, 21 women) with DSM-IV diagnoses of schizophrenia or sc...