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	Li J, 2006(c)16389593
Citation	Li J., Wang Y., Zhou R., Zhang H., Yang L., Wang B. and Faraone S. V. (2006) "Association between tryptophan hydroxylase gene polymorphisms and attention deficit hyperactivity disorder in Chinese Han population." Am J Med Genet B Neuropsychiatr Genet, 141B(2): 126-9.
Study Design	family-based
Study Type	Candidate-gene association study
Sample Size	362 unrelated complete trios
Predominant Ethnicity	Mongoloid
Population	China
Gender	303 (83.7%) male probands and 59 (16.3%) female probands
Age Group	Children/Adolescents : 6-17 years, mean age 10.3, SD=2.6 years

Detail Info

Summary	The current study examined the relationship between the A218C and A-6526G polymorphisms of the TPH gene and ADHD. Three hundred sixty-two unrelated ADHD probands and their biological parents were recruited to participate in this study. No biased transmission of any allele of the two polymorphisms was observed using TDT analysis. However, haplotype analyses found that the rare 218A/-6526G haplotype was significantly not transmitted to probands with ADHD, regardless of subtype. Although this finding for ADHD in the Chinese Han population.
Total Sample	Three hundred and sixty-two unrelated complete trios of ADHD probands and both parents were recruited from the child psychiatric clinics at Peking University Institute of Mental Health from September 1999 to April 2003.
Sample Collection	Han Chinese
Diagnosis Description	Diagnoses of ADHD and subtypes of ADHD were based on the USAn Clinical Diagnostic Interview Scales (CDIS) [Barkley, 1998], a structured interview derived from the DSMIV. Additionally, teachers completed the Rutter Scale to evaluate the children's behaviors in the school environment. Based upon data collected from the CDIS, parent interviews and teacher reports, consensus diagnoses were assigned to all probands. Of the 362 ADHD trios, 150 (41.4%) children met criteria for ADHD-C, 23 (6.4%) met criteria for ADHD-HI, and 189 (52.2%) children met criteria for ADHD-I.
Technique	The peripheral venous blood samples were refrigerated at 4^oC in EDTA-containing test tubes. Genomic DNA was extracted using standard method within 2 weeks. A218C Polymorphism Typing: Forward primer 5'-TTCAGA TCC CTT CTA TAC CCC AGA- 3' and reverse primer 5'-GGA CAT GAC CTA AGA GTT CAT GGC A-3' were used to generate 918 bp fragments of A218C polymorphism. A 25-ul reaction was performed according to the protocol previously described [Nielsen et al., 1997] on a PE- 9700 or a PE-2400 thermal cycler (Perkin Elmer Company, Branchburg, New Jersey). After digestion, the A-variant was cut into two fragments of 860 bp and 58 bp, while the C-variant was cut into three fragments of 615 bp, 245 bp, and 58 bp. A-6526G Polymorphism Typing: Forward primer 5'-TGGCAT TGAAGTAAGAGCAC-3' and reverse primer 5'-GTT TCA TGC AGG TAT TAG TG-3' were used to generate 280 bp fragments of A-6526G polymorphism. A 25-ul reaction was performed according to the protocol previously described [Rotondo et al., 1999]. After digestion, the G-variant was un-cut, while the A-variant was cut into two fragments of 194 bp and 86 bp.
Analysis Method	They used the transmission disequilibrium test (TDT) to assess linkage and association of the two TPH polymorphisms with ADHD. The TDT uses the McNemar X² test to compare the probability of transmission of parental alleles to affected offspring. The McNemar X² test was done using SPSS (release 11.0, SPSS, Inc., Chicago, IL). They also analyzed haplotypes using the TRANSMIT program [version 2.5; Clayton, 1999].
Result Description	No biased transmission of any allele of the two polymorphisms was observed using TDT analysis. However, haplotype analyses found that the rare 218A/-6526G haplotype was significantly not transmitted to probands with ADHD (X²=4.4995, P-value=0.034), regardless of subtype. Although this finding for ADHD in the Chinese Han population.

Other variant reported by this study (count: 2)

Variant Name	Allele Change	Risk Allele	Statistical Values	Author Comments	Result of Statistical Analysis
TPH1 promoter A-6526G	A/G		TDT P-value=0.297, McNemar X²=1.086 for ADHD phen...... TDT P-value=0.297, McNemar X²=1.086 for ADHD phenotype; TDT P-value=0.263, McNemar X²=1.252 for ADHD-C phenotype; TDT P-value=0.424 for ADHD-HI phenotype; TDT P-value=0.932, McNemar X²=0.007 for ADHD-I phenotype More...	no biased transmission of any allele was observed	Non-significant
TPH1 intron7 A218C	C/A		TDT P-value=0.882, McNemar X²=0.022 for ADHD phen...... TDT P-value=0.882, McNemar X²=0.022 for ADHD phenotype; TDT P-value=0.811, McNemar X²=0.057 for ADHD-C phenotype; TDT P-value=0.572, McNemar X²=0.321 for ADHD-HI phenotype; TDT P-value=0.84, McNemar X²=0.041 for ADHD-I phenotype More...	no biased transmission of any allele was observed	Non-significant

Genes reported by this study (count: 1)