No evidence of linkage or association between the norepinephrine transporter (NET) gene MnlI polymorphism and adult ADHD.

Attention deficit hyperactivity disorder (ADHD) is a prevalent psychiatric condition in children and follow-up studies have indicated that one to two thirds of patients continue to suffer from ADHD during late adolescence and adulthood. The mechanism of action of the new selective noradrenergic reuptake inhibitor, atomoxetine, efficacious in the treatment of ADHD symptoms, suggests that the norepinephrine transporter (NET) may be involved in ADHD. The aim of this study was to investigate for the presence of linkage disequilibrium between the MnlI RFLP in the NET gene and adult ADHD in a sample of nuclear families. The MnlI polymorphism was typed in 128 trios and analyzed using the transmission disequilibrium test (TDT). There was no preferential transmission of either allele (chi(2) = 0.209, df = 1, P = 0.647). Copyright 2003 Wiley-Liss, Inc.