Examination of Biopsychosocial Factors of Obesity in a Population-based Cohort: Personality Traits, Eating Behaviour, Physical Activity, and DRD2 Taq1 Gene

Introduction: Dopamine receptor type 2 gene (DRD2 Taq1A, Taq1B and Taq1D) and psychosocial factors such as eating behaviour and physical activity engagement have been demonstrated by past studies to impact obesity, and eventually affect health status and quality of life. However, personality traits were largely examined as a direct or indirect risk factor for obesity with inconclusive results. Hence, this study investigates the predictive effect of Five Factor personality traits on psychosocial factors related to obesity (i.e., level and motives of physical activity, and eating behaviour) besides examining the association of Five Factor personality traits with DRD2 genotypes. Materials and methods: 394 participants (125 males and 269 females) from Universiti Tunku Abdul Rahman (UTAR), Malaysia participated in this study, which involved obtaining anthropometric measurements, mouthwash samples and responses across three scaled items. A genotypic and allelic variance of the DRD2 Taq1 gene was conducted by examining the Restriction Fragment Length Polymorphism using the PCR method. Results: In the eating behaviour domain, Conscientiousness, Extraversion and Neuroticism significantly predicted Uncontrolled Eating (UE) and Emotional Eating (EE). In the physical activity domain, Extraversion positively predicted Total IPAQ score. Conscientiousness, Extraversion and Agreeableness significantly predicted motives for physical activity. The genotypic and allele analysis results showed that participants with higher Neuroticism were significantly different on the ANKK1/DRD2 Taq1A and DRD2 Taq1B. Conclusion: Personality traits could be an aspect to be incorporated into tailoring biopsychosocial obesity management programmes.