ADHDgene Database
  • Published Variant
  • Published Gene: 359
  • Published Region: 128
  • Pathway by PBA: 8
  • Study: 361

Meta-analysis Report

Basic Info
Reference Li D, 200616774975
Citation Li D., Sham P. C., Owen M. J. and He L. (2006) "Meta-analysis shows significant association between dopamine system genes and attention deficit hyperactivity disorder (ADHD)." Hum Mol Genet, 15(14): 2276-84.
Study Type Candidate association study
Summary Molecular genetic investigations of attention deficit hyperactivity disorder (ADHD) have found associations with a variable number of tandem repeat (VNTR) situated in the 3'-untranslated region of dopamine transporter gene (DAT1), a VNTR in exon 3 of dopamine receptor 4 gene (DRD4 ) and a microsatellite polymorphism located at 18.5 kb from the 5' end of dopamine receptor 5 gene (DRD5). A number of independent studies have attempted to replicate these findings but the results have been mixed, possibly reflecting inadequate statistical power and the use of different populations and methodologies. In an attempt to clarify this inconsistency, they have combined all the published studies of European and Asian populations up to October 2005 in a meta-analysis to give a comprehensive picture of the role of the three dopamine-related genes using multiple research methods and models. The DRD4 7-repeat and 5-repeat alleles as well as the DRD5 148-bp allele confer increased risk of ADHD, whereas the DRD4 4-repeat and DRD5 136-bp alleles have protective effects. In contrast, they found no compelling evidence for association with the 480-bp allele of DAT. No significant publication bias was detected in current studies. In conclusion, there is a statistically significant association between ADHD and dopamine system genes, especially DRD4 and DRD5.

Detail Info

Genes reported by this study: 3