To investigate the association between the polymorphism (rs1801260) in ADHD, two samples of ADHD probands from the United Kingdom (n = 180) and Taiwan (n = 212) were genotyped and analysed using within-family transmission disequilibrium test (TDT).
There was a strong, significant association (P < 0.001) between each of the adult ADHD assessments and the rs1801260 polymorphism with at least one T-mutation being the risk allele.