Relationship between Taq1A Dopamine D2 Receptor Polymorphism and Motivation to Exercise andlevels of Voluntary Physical Activity

Aims: The purpose of this study was to examine the genetic basis underlying voluntary physical activity. This study explores to an association, if exists, between motivation to exercise, levels of voluntary physical activity and Taq1A gene polymorphisms. Method: 122 participants (age=24.4±5.7 yrs., 55 males & 67 females) completed the Behavioral Regulation in Exercise Questionnaire – 2 (BREQ-2) to assess their motivation to exercise and the International Physical Activity Questionnaire (IPAQ) to assess their level of physical activity. DNA was isolated from a cheek cell sample. The Taq1A genotype was identified using PCR with gene specific primers. Results: Our study included 85 normal-weight, 30 overweight, and 7 obese subjects. Three variants of DRD2 taq1A -CC (n=77, 63.1%), CT (n=35, 7.28%), and TT (n=10, 2.8%) - were identified. Internal motivation to exercise was significantly higher in the CC genotype compared to the other two genotypes (P=0.017). Conclusion: In general, intrinsic regulation factors of motivation, as well as the type of genotype, may play a major role in determining the level of physical activity. Taq1A polymorphism of the DRD2 gene is related to physical activity and body weight in young men and women.