• Also known as C-521T and -521C/T, is a variant in the promoter region upstream of the DRD4 gene.
  • The C allele increases DRD4 gene expression by 40% compared to the T allele (R). The C-allele increases the DRD4 transcriptional efficiency [R].

The presence of the C allele (in carriers of the COMT A/A genotype) showed high levels of extraversion and hypomania (R).

The C allele has been associated with novelty-seeking [R].

The C allele has been associated with Extraversion [R].

CC females, but not the males, were more "rational" and less "emotional" in decision-making processes than the T-allele carriers. "Increase in dopamine availability enhances the cognitive and reduces the emotional components of moral decision-making in females, thus favoring a more rationally-driven decision process." [R]

We detected, and then replicated a significant association between the DRD4 -521CC genotype and sports-specific sensation seeking as measured using the CSSQ-S (P < 0.001). These data suggest that the DRD4 -521 C/T polymorphism contributes to a "risk-taking phenotype" in skiers and snowboarders, but the variant was not associated with impulsive sensation seeking (P = 0.9) [R].

The T-allele has been associated with attention deficits (Yang et al., 2008).

rs1800955 and rs1800443 are discussed in this article as influencing personality.


Parent Gene: DRD4

Importance: 5
Less common allele: C = 41%
More common allele: T = 59%
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