ADHDgene Database

Hot Results

Quick Search

Keyword:
Type:

Large-scale studies

Data Summary

Published Variant
- SNP: 1391
- CNV: 398
- Others: 173
Published Gene: 359
Published Region: 128
Pathway by PBA: 8
Study: 361

Study Report

Basic Info

Reference	Banoei MM, 200817582621
Citation	Banoei M. M., Majidizadeh T., Shirazi E., Moghimi N., Ghadiri M., Najmabadi H. and Ohadi M. (2008) "No association between the DAT1 10-repeat allele and ADHD in the Iranian population." Am J Med Genet B Neuropsychiatr Genet, 147B(1): 110-1.
Study Design	case-control
Study Type	Candidate-gene association study
Sample Size	100 cases and 130 controls
Predominant Ethnicity	Iranian
Population	Iran
Gender	70 males for cases, 80 males for controls
Age Group	Children/Adolescents : mean age 10,SD=4 for cases, mean age 12,SD=5 for controls

Detail Info

Summary	Association studies between attention-deficit hyperactivity disorder (ADHD) and the 10-repeat allele of a polymorphism (a 40 bp variable number of tandem repeats) in the dopamine transporter gene (DAT1) have resulted in mixed findings in different populations. They performed a case/control study to clarify the contribution of this allele with ADHD in the Iranian population. No association was observed between the 10-allele and disease (x²=0.081, P-value<0.9). Furthermore, no significant difference was observed in the homozygosity of this allele between the case and control groups (x²=0.022, P-value<0.9). Implication of the dopamine transporter gene in the pathophysiology of ADHD warrants investigation of other functional polymorphisms within this gene in the Iranian ADHD patients.
Total Sample	One hundred unrelated Iranian subjects (70 males) with ADHD were recruited for the study from the Child Psychiatry Clinic of the Rassool Akram Hospital-Iran Medical Sciences University and two private clinics in Tehran. One hundred thirty unrelated Iranian children (80 males) were randomly selected as controls.
Sample Collection	Iranian
Diagnosis Description	All the patients in this study met the following criteria using Diagnostic and Statistical Manual of Mental Disorders (DSM-IV): six symptoms of inattention and/or hyperactivity/ impulsiveness either in the home or school setting as determined by clinical interview; evidence of pervasiveness, defined as a minimum of four symptoms in the noncriterion setting, and onset before 7 years of age.
Technique	A 10 ml buccal sample was drawn from each subject. DNA was extracted using standard techniques and subsequently used as a template for the determination of DAT1 VNTR alleles by polymerase chain reaction as described previously [Holmes et al., 2000]. Approximately 100 ng of amplified DNA were analyzed by electrophoresis on a 4% polyacrylamide gel and visualized following silver staining.
Analysis Method	The Chi-square test was employed to compare frequency differences of the VNTR alleles and genotypes between the groups studied. A P-value of <=0.02 was considered significant; implementing the Bonferroni 0.5 mean correction to the conventional significant P-value of <0.05.
Result Description	No association was observed between the 10-allele and disease. Furthermore, no significant difference was observed in the homozygosity of this allele between the case and control groups.

Other variant reported by this study (count: 1)

Genes reported by this study (count: 1)