A case-control association study of the polymorphism at the promoter region of the DRD4 gene in Korean boys with attention deficit-hyperactivity disorder: evidence of association with the -521 C/T SNP.

Abstract

Recent genetic studies at the 5' end of the dopamine D4 receptor (DRD4) gene have identified several polymorphisms having a possible relationship with attention deficit-hyperactivity disorder (ADHD). This study examined the association between the -521 and -376 promoter single nucleotide polymorphisms (SNPs) of the DRD4 gene and ADHD through a case-control association study in Korean boys, who constitute a single ethnic population. Ninety-four ADHD and ninety-five control boys were enrolled in this study. All of the ADHD subjects completed a comprehensive and standardized diagnostic and psychological evaluation battery including the ADHD Rating Scale-IV (ARS). Genotyping for the 2 promoter SNPs was performed. There were significant differences in the genotype and allele frequencies of the -521 C/T SNP between the ADHD and control groups (chi2=6.28, p=0.043 and chi2=6.22, p=0.013, respectively). However, the distribution of the -376 C/T genotypes and alleles were similar in the ADHD and control groups. The subtypes of ADHD were not related to either of these two SNPs. In the ADHD subjects, the -521 TT genotype group had a higher score in the inattentive subscale and a lower score in the hyperactive subscale of the parents version of ARS, although these differences did not attain statistical significance (p=0.146, p=0.082). In conclusion, there was a significant association between the -521 C/T SNP and ADHD in Korean boys. These results suggest a role of the -521 C/T SNP in the susceptibility for ADHD.

• Authors: Jae-Won Yang, Won-Seok Jang, Sungdo David Hong, Yong Ick Ji, Duk Hwan Kim, Jubae Park, Swon Woo Kim, Yoo Sook Joung
• Journal: Progress in neuro-psychopharmacology & biological psychiatry (Prog Neuropsychopharmacol Biol Psychiatry) Vol. 32 Issue 1 Pg. 243-8 (Jan 01 2008) ISSN: 0278-5846 [Print] England
• PMID: 17850946 (Publication Type: Journal Article)

Chemical References

• DRD4 protein, human
• Receptors, Dopamine D4

Topics

• Attention Deficit Disorder with Hyperactivity (classification, genetics)
• Case-Control Studies
• Chi-Square Distribution
• Child
• Gene Frequency
• Genetic Predisposition to Disease
• Genotype
• Humans
• Korea
• Male
• Polymorphism, Single Nucleotide (genetics)
• Promoter Regions, Genetic
• Psychiatric Status Rating Scales
• Receptors, Dopamine D4 (genetics)
• Statistics, Nonparametric