Association of self-report measures of psychosis proneness and the COMT gene Val158Met polymorphism

Abstract

The association of COMT Va1158Met polymorphism to psychosis proneness was examined along with the potential confound of social desirability, and its relationship to the valid assessment of psychosis-related traits. The catecholo-methyltransferase (COMT) genotype, which has been linked to psychopathology and personality traits is correlated with scores from a set of self-report measures of personality and psychopathology. It goes beyond these prior studies in examining the role of socially desirable responding in modulating these associations. The present study explored the effects that these associations might have on their relationships to COMT genotype. It examined the relationship between COMT genotype and traits related to the susceptibility to psychosis. Self report measures of these traits included the Social Anhedonia subscale of the Chapman' Psychosis Proneness Scale as well as scales designed to measure psychotic symptomatology, namely the Symptom Checklist - Revised (SCL-90R) Psychoticism and Paranoia subscales. Differential analyses were included in order to distinguish the association between the genotype and Psychoticism from an association to other types of psychopathology, namely anxiety and depression. These symptoms were assessed using the SCL-90 Anxiety and Depression subscales, as well as the Beck Depression Inventory (BD1-II) scales. Socially desirable responding was assessed using the Balanced Inventory of Desirable Responding (BIDR) Impression Management scale, and was related to both the genotype and to scores on the psychopathology scales.;Data were collected from normal adults (N=403) age 18 to 55 who were assessed at the Department of Biopsychology of New York State Psychiatric Institute. Results indicate that the group homozygous for the Met allele demonstrated significantly higher scores on the Chapman Psychosis Proneness Social Anhedonia scale than Val/Val and Met/Val groups. Additional measures used to measure psychotic traits, namely the Psychoticism and Paranoia subscales of the Symptoms Checklist 90 (SCL-90) questionnaire, demonstrated similar association with the same allelic group. Other measures of psychopathology, as measured by the SCL-90 Depression and Anxiety subscales as well as the BDI-II---had no relationship to the COMT alleles. In addition, the Met/Met group had significantly lower scores on the Impression Management measure of BIDR than the Val/Val group.;Contrary to our belief, controlling for effects of Impression Management, however, did not change the association between the Met/Met allele group and higher scores on the Psychosis proneness self-report measure.