Association between hypnotizability and the catechol-O-methyltransferase (COMT) polymorphism.

Previous studies implicate involvement of dopaminergic systems in hypnotizability and report association with the COMT Val(158)Met single nucleotide polymorphism (SNP, rs4680) demonstrating the Val/Met heterozygotes as the most hypnotizable group using the Stanford Hypnotic Susceptibility Scale. This study replicates that association using an independent sample of 127 healthy Hungarian young adults and the Waterloo-Stanford Group C Scale of Hypnotic Susceptibility. Significant association (p = .016) was found between the COMT genotypes and hypnotizability, with a clear additive effect of the Val allele: Hypnotizability scores were highest in Val/Val (5.9), intermediate in Val/Met (4.7), and lowest in Met/Met (4.1). Differences between these results and those of previous studies support recent findings suggesting an inverted-U-shaped relation between dopamine level in the prefrontal cortex and cognitive functioning. The present study replicates association of COMT Val(158)Met SNP and hypnotizability and stresses the importance of mediating factors, such as group vs. individual inductions.