This study provides the first estimate of the heritability of DD in humans. Using a real-money choice paradigm, this study demonstrated that individual differences in the discounting of delayed gratification among adolescents are moderately to strongly influenced by genetic factors at ages 12 and 14 respectively. The results also suggest an increasing role of genetic factors with age. Given that DD is considered to be one of the key components of a broader impulsivity trait (Perry and Carroll 2008; de Wit 2009), the demonstration of a significant genetic component in DD has important implications for genetic studies of psychopathological conditions characterized by increased impulsivity, particularly those involving impulsive decision-making, such as addictions, pathological gambling, externalizing disorders, and ADHD.
