Abstract
A relatively common stop codon (Q20*) was identified in the serotonin 2B receptor gene (HTR2B) in a Finnish founder population in 2010 and it was associated with impulsivity. Here we examine the phenotype of HTR2B Q20* carriers in a setting comprising 14 heterozygous HTR2B Q20* carriers and 156 healthy controls without the HTR2B Q20*. The tridimensional personality questionnaire, Brown-Goodwin lifetime aggression scale, the Michigan alcoholism screening test and lifetime drinking history were used to measure personality traits, impulsive and aggressive behavior, both while sober and under the influence of alcohol, and alcohol consumption. Regression analyses showed that among the HTR2B Q20* carriers, temperamental traits resembled a passive-dependent personality profile, and the presence of the HTR2B Q20* predicted impulsive and aggressive behaviors particularly under the influence of alcohol. Results present examples of how one gene may contribute to personality structure and behaviors in a founder population and how personality may translate into behavior.