Objectives: The aims of this study were (i) to examine genotypic association of the catechol-O-methyltransferase (COMT) val158met polymorphism with anxiety-related traits with a meta-analysis; (ii) to examine sex and ethnicity as moderators of the association; and (iii) to evaluate whether the association differed by particular anxiety traits.
Methods: Association studies of the COMT val158met polymorphism and anxiety traits were identified from the PubMed or PsycInfo databases, conference abstracts, and listserv postings. Exclusion criteria were (a) pediatric samples, (b) exclusively clinical samples, and (c) samples selected for a nonanxiety phenotype. Standardized mean differences in anxiety between genotypes were aggregated to produce mean effect sizes across all available samples, and for subgroups stratified by sex and ethnicity (Whites vs. Asians). Construct-specific analysis was conducted to evaluate the association of COMT with neuroticism, harm avoidance, and behavioral inhibition.
Results: Twenty-seven eligible studies (N=15 979) with available data were identified. Overall findings indicate sex-specific and ethnic-specific effects: valine homozygotes had higher neuroticism than methionine homozygotes in studies of White males [mean effect size
=0.13; 95% CI 0.02, 0.25; P=0.03], and higher harm avoidance in studies of Asian males (
=0.43; 95% CI 0.14, 0.72; P=0.004). No significant associations were found in women and effect sizes were diminished when studies were aggregated across ethnicity or anxiety traits.
Conclusion: This meta-analysis provides evidence for sex and ethnic differences in the association of the COMT val158met polymorphism with anxiety traits. Our findings contribute to current knowledge on the relation between prefrontal dopaminergic transmission and anxiety.
aDepartment of Epidemiology, Boston University School of Public Health
bNational Center for Posttraumatic Stress Disorder, Veterans Affairs Boston Healthcare System, Boston, Massachusetts
cDepartment of Psychology and Davis School of Gerontology, University of Southern California, Los Angeles, California, USA
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Correspondence to Lewina O. Lee, PhD, National Center for Posttraumatic Stress Disorder, Veterans Affairs Boston Healthcare System, 150 South Huntington Avenue (151-C), Boston, MA 02130, USA Tel: +1 857 364 6364; fax: +1 857 364 4424; e-mail: firstname.lastname@example.org
Received March 24, 2013
Accepted September 6, 2013