title: The lack of association between monoamine oxidase (MAO) intron 13 polymorphism and platelet MAO-B activity among men.
abstract: Monoamine oxidase (MAO), a mitochondrial flavine containing enzyme, exists in two isoenzymes, MAO-A and MAO-B. Platelets contain MAO-B subtype, proposed to be a biomarker for different personality characteristics and vulnerability for substance abuse. The most common polymorphism of MAO-B gene, a single base change (A or G) occurs in intron 13. It has been proposed to be a functional polymorphism, controlling the activity of MAO-B in platelets. The aim of the study was to determine the association between platelet MAO-B activity and MAO-B intron 13 polymorphism in 225 racially and ethnically uniform healthy Caucasian men of the Croatian origin. Our results showed that platelet MAO-B activity did not differ between subjects subdivided into those with <<A-allele>> or <<G-allele>>. This polymorphism of the MAO-B gene did not control the activity of the MAO-B in platelets. Platelet MAO-B activity was associated only with the smoking status, and it was significantly decreased in smokers when compared to nonsmokers. No significant association was found between MAO-B polymorphism and smoking status. In healthy individuals of the Croatian origin, the studied MAO-B polymorphism showed a lack of functional importance in regulating MAO-B activity in platelets. Since different populations may vary in the association between functional polymorphism and the MAO-B activity, and the genotype of transcription factor AP-2 beta was reported to be associated with altered platelet MAO-B activity, and with specific personality traits, further studies on different populations should be conducted to elucidate the molecular mechanism/s regulating platelet MAO-B activity.
authors.affiliation: Division of Molecular Medicine, Rudjer Boskovic Institute, PO Box 180, HR-10002 Zagreb, Croatia. npivac@irb.hr
authors.forename: Nela
authors.initials: N
authors.lastname: Pivac
authors.forename: Jelena
authors.initials: J
authors.lastname: Knezevic
authors.forename: Maja
authors.initials: M
authors.lastname: Mustapic
authors.forename: Martina
authors.initials: M
authors.lastname: Dezeljin
authors.forename: Dorotea
authors.initials: D
authors.lastname: Muck-Seler
authors.forename: Dragica
authors.initials: D
authors.lastname: Kozaric-Kovacic
authors.forename: Melita
authors.initials: M
authors.lastname: Balija
authors.forename: Tanja
authors.initials: T
authors.lastname: Matijevic
authors.forename: Jasminka
authors.initials: J
authors.lastname: Pavelic
mesh_terms: D000328:Adult; D001792:Blood Platelets / Q000201:enzymology*; D017523:Croatia; D004247:DNA / Q000096:biosynthesis / Q000235:genetics; D005838:Genotype; D006801:Humans; D007438:Introns / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D008995:Monoamine Oxidase / Q000235:genetics*; D011110:Polymorphism, Genetic / Q000235:genetics*; D012907:Smoking / Q000378:metabolism; D050656:Transcription Factor AP-2 / Q000235:genetics
chemical_list: D050656:Transcription Factor AP-2; D004247:DNA; D008995:Monoamine Oxidase