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Dopamine D4 gene 7-repeat allele and attention deficit hyperactivity disorder
S V Faraone1, J Biederman, B Weiffenbach
1Pediatric Psychopharmacology Unit of the Child Psychiatry Service, Massachusetts General Hospital, Boston 02114, USA.
The American Journal of Psychiatry
|May 18, 1999
Summary
Attention deficit hyperactivity disorder (ADHD) is linked to the DRD4 gene, specifically the 7-repeat allele. This genetic finding was observed in families with clinically referred ADHD adults and their children.
Area of Science:
- Genetics
- Neuroscience
- Psychiatry
Background:
- Attention deficit hyperactivity disorder (ADHD) has a significant genetic basis, supported by family, twin, and adoption studies.
- Previous research suggests a potential link between ADHD and the dopamine D4 (DRD4) gene.
Purpose of the Study:
- To investigate the association between ADHD and the DRD4 gene in families.
- To determine if the DRD4 7-repeat allele is specifically linked to ADHD diagnosis.
Main Methods:
- Recruited 27 triads, each including an ADHD adult, their spouse, and their ADHD child.
- Assessed participants for ADHD and performed DNA genotyping for DRD4 alleles.
Main Results:
- A transmission disequilibrium test indicated an association between ADHD and the DRD4 7-repeat allele.
- The number of DRD4 7-repeat alleles correlated with ADHD diagnosis within families.
Conclusions:
- The association between ADHD and the DRD4 gene is confirmed in families with clinically referred ADHD adults.
- Further research is necessary to fully elucidate the role of DRD4 in the development of ADHD, given some conflicting findings.
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