Association between catechol-O-methyltransferase Val¹⁵⁸Met polymorphism and configural mode of face processing

Human visual system heavily relies on the spatial configuration among facial parts in discriminating faces. There are individual differences in the ability of configural face processing, which are supposed to be partly attributable to genetic predispositions. However, few studies have identified a specific gene linked to configural face processing ability. The present study investigated an association between configural mode of face processing and a single-nucleotide polymorphism in codon 158 of catechol-O-methyltransferase gene (COMT Val(158)Met polymorphism) using part-spacing paradigm. The results have revealed superior sensitivity to the changes in facial configuration in participants with Met/Met genotype of COMT Val(158)Met polymorphism compared to the other genotypes. This effect was virtually eliminated when the faces were presented upside-down. There was no group-difference in the ability to detect the change in morphological features of individual facial parts. These results indicate that COMT Val(158)Met polymorphism partly explains the individual differences in the ability of configural face processing.