COMT gene val158met polymorphism in patients with dyspeptic symptoms

Background/Aims: The role of genetics in the susceptibility to functional dyspepsia (FD) is unclear. Catechol-O-methyltransferase (COMT) has been an important enzyme in brain gut axis and pain sensitivity. Polymorphism in codon 158 of the COMT gene influences its activity. This study aimed to clarify the association between COMT polymorphism and dyspepsia in a Japanese population. Methodology: 91 dyspeptics and 94 non-dyspeptic subjects enrolled in this study. Dyspeptic symptoms were divided into 9 categories. COMT gene val158met polymorphism was determined by polymerase chain reaction-restriction fragment length polymorphism. Results: The frequency of Met carriers was lower in over all dyspeptics than healthy control but the difference was not significant (OR=0.79, 95%CI=0.44-1.41) However, when the interaction between age, gender, H. pylori infection status and the number of COMT 158Met alleles was assessed using ANOVA, a slight interaction with gender + age + COMT polymorphism was found in relation to overall dyspeptics (p=0.0476) No correlation was found between COMT polymorphism and any of 9 symptoms. Conclusions: The data suggest that the COMT genotype seems to influence the susceptibility of dyspepsia when it interacts with gender and age. The role of genetics in the development of dyspepsia needs to further evaluation.