Molecular genetic contribution to the developmental course of attention-deficit hyperactivity disorder

  • Kate Langley
  • Tom A. Fowler
  • Deborah L. Grady
  • Robert K. Moyzis
  • Peter A. Holmans
  • Marianne B. M. van den Bree
  • Michael J. Owen
  • Michael C. O’Donovan
  • Anita Thapar
ORIGINAL CONTRIBUTION

DOI: 10.1007/s00787-008-0698-4

Cite this article as:
Langley, K., Fowler, T.A., Grady, D.L. et al. Eur Child Adolesc Psychiatry (2009) 18: 26. doi:10.1007/s00787-008-0698-4

Abstract

Objective

The developmental trajectory of attention-deficit hyperactivity disorder (ADHD) is variable. Utilizing a longitudinally assessed sample, we investigated the contribution of susceptibility gene variants, previously implicated through pooled or meta-analyses, to the developmental course of Attention-Deficit Hyperactivity Disorder over time.

Methods

151 children (aged 6–12) who met diagnostic criteria for ADHD were assessed using research diagnostic interviews during childhood and 5 years later in adolescence. Severity was defined as total number of ADHD symptoms at baseline and reassessment. Association with variants at DRD4, DRD5, and the dopamine transporter gene, DAT was analyzed using linear regression.

Results

As expected, affected individuals showed a decline in ADHD severity over time. The DRD4 48 bp VNTR 7-repeat and DRD5 CA(n) microsatellite marker 148 bp risk alleles were associated with persistent ADHD. Those possessing the DRD4 7 repeat risk allele showed less of a decline in severity at reassessment than those without the risk allele.

Conclusions

Those carrying the DRD4 7 risk allele showed greater symptom severity at follow-up and less ADHD reduction over time. These findings support the hypothesis that some susceptibility genes for ADHD also influence its developmental course.

Keywords

ADHDlongitudinalDRD4DRD5DAT1

Copyright information

© Steinkopff Verlag 2009

Authors and Affiliations

  • Kate Langley
    • 1
  • Tom A. Fowler
    • 1
  • Deborah L. Grady
    • 2
  • Robert K. Moyzis
    • 2
    • 3
  • Peter A. Holmans
    • 1
  • Marianne B. M. van den Bree
    • 1
  • Michael J. Owen
    • 1
  • Michael C. O’Donovan
    • 1
  • Anita Thapar
    • 1
  1. 1.Department of Psychological Medicine, School of MedicineCardiff UniversityCardiffUK
  2. 2.Department of Biological ChemistryUniversity of CaliforniaIrvineUSA
  3. 3.Institute of Genomics and BioinformaticsUniversity of CaliforniaIrvineUSA