Dopamine genes and ADHD

https://doi.org/10.1016/S0149-7634(99)00062-7Get rights and content
Under a Creative Commons license
open archive

Abstract

Family, twin, and adoption studies have documented a strong genetic basis for ADHD/HKD, but these studies do not identify specific genes linked to the disorder. Molecular genetic studies can identify allelic variations of specific genes that are functionally associated with ADHD/HKD, and dopamine genes have been the initial candidates based on the site of action of the stimulants drugs, which for a half century have provided the primary pharmacological treatment for ADHD/HKD. Two candidate dopamine genes have been investigated and reported to be associated with ADHD/HKD: the dopamine transporter (DAT1) gene [Cook et al., American Journal of Human Genetics 1995;56:993–998, Gill et al., Molecular Psychiatry 1997;2:311–313] and the dopamine receptor D4 (DRD4) gene [LaHoste et al., Molecular Psychiatry 1996;1:121–124; Smalley et al., 1998;3:427–430; Swanson et al., Molecular Psychiatry 1998;3:38–41]. Speculative hypotheses [Swanson and Castellanos, NIH Consensus Development Conference: Diagnosis and Treatment of Attention Deficit Hyperactivity Disorder, November 1998. p. 37–42] have suggested that specific alleles of these dopamine genes may alter dopamine transmission in the neural networks implicated in ADHD/HKD (e.g. that the 10-repeat allele of the DAT1 gene may be associated with hyperactive re-uptake of dopamine or that the 7-repeat allele of the DRD4 gene may be associated with a subsensitive postsynaptic receptor). These and other variants of the dopamine hypothesis of ADHD will be discussed.

Keywords

Dopamine genes
ADHD
Alleles

Cited by (0)

Presented at INABIS ‘98—Fifth Internet World Congress on Biomedical Sciences at McMaster University, Canada, 7–16 December. Invited Symposium. After the symposium, a review of the tables resulted in some minor corrections but none of these changed the conclusions of the poster. Available at URL http://www.mcmaster.ca/inabis98/sadile/swanson0770/index.html. © 1998, author(s) hold copyright.

Supported by grants from the Irvine Health Foundation and from NIH for a Mental Retardation Developmental Disabilities Research Center (HD 28202).