| The present researcher examined the genetic relationship between depression and anxiety. Several researchers have investigated the issue using traditional approaches (i.e., twin, adoption, and family studies) and have revealed evidence that suggests that these two disorders share a common genetic factor (e.g., Kendler et al., 1995). To explore the association further, this investigator used a biological marker, 6-n-propylthiouracil (PROP), to investigate whether participants who report experiencing depressive and anxiety symptoms or a family history of such differ from those individuals who report no symptomatology in taste sensitivity to PROP.; Two hundred college students were assigned to six groups based on their own diagnostic classification and/or that of their parents: Depression Group, Anxiety Group, Mixed Depression/Anxiety Group, Substance/Alcohol Abuse Group, Mixed Substance Abuse/Depression/Anxiety Group, and Control Group. Participants were asked to take a taste test using filter paper saturated with PROP and to indicate their judgment of its taste intensity. Approximately 75% of the population are considered tasters and the remaining 25% can taste PROP only at the strongest concentrations; 33% of tasters (about 25% of the general population) are considered supertasters, extremely sensitive to the taste of PROP (Bartoshuk, 1993). The PROP test was used in this study to identify individuals as nontasters (25%), medium tasters (50%), and supertasters (25%). The results showed that the taste status distribution of the Depression Group, the Mixed Depression/Anxiety Group, and the Mixed Substance Abuse/Depression/Anxiety Group differed significantly from the Control Group's distribution (25:50:25). The Mixed Depression/Anxiety Group had more medium tasters and supertasters, whereas a significant taste subgroup difference could not be determined statistically for the Depression Group or the Mixed Substance Abuse/Depression/Anxiety Group.; Students' psychological history was separated from their parents' psychological history, statistically establishing parent groups and student groups. The results showed that the taste status distribution of the Parent Depression Group, the Parent Anxiety Group, and the Parent Alcohol Abuse Group differed significantly from the Control Group's distribution (25:50:25). A significant taste subgroup difference, however, was found only for the Parent Anxiety Group (more supertasters).; Three student groups were found to be significantly different in taste status distribution when compared with the Control Group's distribution (25:50:25): the Student Depression Group, the Student GAD Group, and the Student Depression/Anxiety Group. All three groups were found to have significantly more supertasters.; The investigator concluded that individuals with a family history of anxiety or who themselves experience depressive or anxiety symptoms, or a combination of both symptomatology tend to share a similar taste sensitivity trend (supertaster status). |
