COMT Val158Met polymorphism associated with greater susceptibility to framing effects in healthy older adults

Abstract

Age-related neural changes may compromise older adults decision-making, increasing their risk of fraud and financial abuse. One manifestation of nonrational influences on decision-making is susceptibility to \"framing effects,\" in which decisions are biased by irrelevant contextual features of how choice information is presented. We investigated whether polymorphisms in genes related to dopamine neurotransmission (COMT) and neurodegeneration (ApoE) influence the susceptibility of older adults to framing effects. We administered an online test of susceptibility to framing effects to a cohort of 113 healthy older adults who had undergone genetic testing for COMT and ApoE genotype. The task required the participant to choose a risky or safe option in pairs of situations that were monetarily equivalent but differed in whether the choice was framed in terms of gains or losses. A general linear model was used to test for associations between inconsistency in choice across the set of choice pairs and these genotypes, controlling for age, education, gender and traditional measures of executive function. While no association to framing effects was found for ApoE, the Valine allele of COMT Val158Met was significantly associated with greater susceptibility to framing, although the association was no longer significant after adjustment for demographic covariates. Our results suggest that greater frontal dopamine concentrations associated with the COMT Met allele are protective against less consistent decision making in older adults. When compared to previous findings in young adults, our findings provide additional support for an inverted-U shaped model of prefrontal dopamine function.