The COMT Val158Met Polymorphism and Exploratory Behavior in Bipolar Mania.

Area of Science:

• Neurogenetics
• Psychiatric Disorders
• Behavioral Science

Background:

• The catechol-O-methyltransferase (COMT) Val158Met gene polymorphism affects cognition and behavior, particularly in psychiatric conditions.
• The low-activity methionine (Met) allele of COMT may correlate with behaviors indicating catecholamine overactivity.
• Bipolar disorder (BD) is characterized by heightened motor activity and positive valence, measurable with the human Behavioral Pattern Monitor (hBPM).

Purpose of the Study:

• To investigate the relationship between COMT Val158Met genotype and behavior in manic bipolar disorder (BD) patients.
• To assess if COMT genotype influences exploratory behavior and object interaction in the hBPM paradigm.
• To explore the role of catecholamine activity in manic BD behavior.

Main Methods:

• Genotyping of the COMT Val158Met polymorphism in 26 acutely hospitalized manic BD patients.
• Testing patients in the hBPM, an unfamiliar environment with novel objects, for 15 minutes.
• Video recording and rating of patient movements and object interactions within the hBPM.

Main Results:

• Met homozygote BD patients showed significantly increased interactions with multiple objects and spent more time exploring them.
• Valine (Val) homozygote BD patients exhibited the least object exploration.
• Heterozygote BD patients displayed intermediate levels of object exploration.

Conclusions:

• Preliminary findings suggest a linear influence of COMT genotype on arousal and positive valence in manic BD, potentially via frontal catecholamine levels.
• These results indicate that COMT genotype may modulate exploratory behavior in BD.
• The hBPM paradigm shows potential for cross-species and transdiagnostic research in psychiatric neurobiology.