Related Experiment Video
Updated: Jul 18, 2026

Comprehensive Profiling of Dopamine Regulation in Substantia Nigra and Ventral Tegmental Area
Published on: August 10, 2012
Dopamine beta-hydroxylase gene (DbetaH) -1021C-->T influences self-reported paranoia during cocaine
Rasmon Kalayasiri1, Atapol Sughondhabirom, Ralitza Gueorguieva
1Department of Psychiatry, Yale School of Medicine, New Haven, Connecticut 06519, USA.
Background:
Variation in the gene for dopamine beta-hydroxylase (DbetaH) has been reported to associate with cocaine-induced paranoia as assessed by retrospective self-report. This association has yet to be tested prospectively.
Methods:
Visual analog scale (VAS) ratings of paranoia were obtained in 31 cocaine users during three cocaine self-administration sessions (8, 16, and 32 mg/70 kg). Pharmacogenetic interactions between cocaine and a putative functional polymorphism in DbetaH (-1021C-->T) were assessed.
Results:
VAS self-ratings showed significant or trend-level interactions of genotype and time during each session (p = .004, .09 and .003, respectively) with TT homozygotes endorsing greater paranoia over time than either CT or CC individuals. Interactions were significant at all doses in African Americans (n = 19; p = .02, .04 and .05). No other demographic or experimental variable distinguished genotypic groups.
Conclusions:
Results indicate that individuals homozygous for the 'very low-activity' T allele at DbetaH -1021C-->T show an increased propensity to paranoia over time during cocaine self-administration.
Related Concept Videos
Human Genetics
The complex relationship between genetics and psychology is observable through common biological components such...
Drugs Affecting Neurotransmitter Synthesis
Drugs Affecting Neurotransmitter Release or Uptake
Psychosis: Pathophysiology of Schizophrenia and Other Psychotic Disorders
Researchers have identified genetic factors that increase susceptibility to schizophrenia, underscoring the intricate interplay between genetics and environment in disease development. At the core of schizophrenia's pathophysiology is excessive dopaminergic neurotransmission within the...
Drug Dependence
Pharmacogenetics of Drug Targets: β₂-Adrenergic Receptors, Apo E, Thymidylate Synthase

