Cookies on this website

We use cookies to ensure that we give you the best experience on our website. If you click 'Accept all cookies' we'll assume that you are happy to receive all cookies and you won't see this message again. If you click 'Reject all non-essential cookies' only necessary cookies providing core functionality such as security, network management, and accessibility will be enabled. Click 'Find out more' for information on how to change your cookie settings.

Elevated plasma total homocysteine (tHcy) is a risk factor for various disorders. We investigated whether functional polymorphisms in catechol-O-methyltransferase (COMT) influence tHcy, since COMT activity produces S-adenosylhomocysteine (SAH), a homocysteine precursor. We hypothesized that high activity COMT variants would be associated with high tHcy, since they presumably result in increased formation of SAH. We genotyped 780 community-dwelling elderly individuals for functional COMT (Val(158)Met and A(-287)G) and methylenetetrahydrofolate reductase (MTHFR; C(677)T) polymorphisms, and measured plasma tHcy. As predicted, COMT Val(158) carriers had significantly higher tHcy than Met(158) homozygotes. The effect was limited to individuals homozygous for the MTHFR T(677) allele. In addition, individuals homozygous for the COMT G(-287) allele tended to have lower tHcy levels. High activity variants of COMT interact with the low activity variant of MTHFR to increase tHcy levels. The effect on tHcy may contribute to the reported associations of COMT genotype with psychiatric and neurobiological phenotypes. The results also indicate that COMT activity may influence a broader range of biochemical pathways than hitherto appreciated.

Original publication

DOI

10.1002/ajmg.b.30700

Type

Journal article

Journal

Am J Med Genet B Neuropsychiatr Genet

Publication Date

05/09/2008

Volume

147B

Pages

996 - 999

Keywords

Aged, Aged, 80 and over, Alleles, Case-Control Studies, Catechol O-Methyltransferase, Epistasis, Genetic, Female, Genotype, Homocysteine, Humans, Linkage Disequilibrium, Male, Methylenetetrahydrofolate Reductase (NADPH2), Middle Aged, Models, Biological, Polymorphism, Single Nucleotide