We carried out a meta-analysis of published studies reporting data on the association between COMT genotype and P300 amplitude and latency. Recall that a potential criticism of our analysis of WCST and N-Back data is that they do not represent a truly biological endophenotype marker. Analysis of the association between COMT genotype and P300 amplitude and latency should provide a best-case scenario for the value of the endophenotype approach in genetics.
