Genetic and Environmental Contributions to Perceived Intensity and Pleasantness of Androstenone Odor: An International Twin Study

We estimated the genetic and environmental components of variation in perceived intensity and pleasantness of androstenone, an odorous compound showing specific anosmia, by modeling twin data from Finland, Denmark, the UK, and Australia. The pooled data comprised 917 twin individuals (338 are male and 579 are female; aged from 10 to 83years) including 126 complete monozygous and 264 dizygous twin pairs as well as 137 twin individuals without their co-twin. They rated intensity and pleasantness of androstenone and citronellal (control) odors using nine categories. Additive genetic effects (heritability) contributed 28 and 21% to the variation in the perceived intensity and pleasantness of androstenone, respectively, but negligibly to variations in citronellal perception. A strong genetic correlation existed between the intensity and pleasantness of androstenone, whereas the environmental correlation was negligible. These results suggest that both intensity and pleasantness of androstenone are moderately influenced by genetic factors and that the traits are modified by an overlapping set of genes.