[Association study of intelligence of attention deficit hyperactivity disorder children in China]

Beijing Da Xue Xue Bao Yi Xue Ban. 2009 Jun 18;41(3):285-90.
[Article in Chinese]

Abstract

Objective: To investigate the association of 5-HT(2A) receptor gene (HTR2A)-1438A/G, Catechol-O-methyltransferase (COMT) gene Val158Met, Monoamine oxidase A ( MAOA ) gene 30 bp-VNTR(MAOA-uVNTR)polymorphisms, and the educational attainment level of the parents with the intelligence of attention deficit hyperactivity disorder (ADHD) in China.

Methods: A total of 485 DSM-IV ADHD children of Chinese Han descent were included, both complete IQ evaluation, HTR2A-1438A/G, COMT gene Val158Met, and MAOA-uVNTR genotyping results were obtained. The quantitative traits of psychometric IQ were calculated by using the Chinese Wechsler Intelligence Scale for Children (C-WISC). The multifactor linear regression analysis was used to test the associated factors on intelligence.

Results: Analyses revealed that ADHD children with low enzymatic activity (3R for males, 3R3R for females) of MAOA-uVNTR performed better on Full Scale IQ (FIQ) than did patients with high enzymatic activity (4R for males, 3R4R/4R4R for females) [(102.6+/-12.4) vs (100.3+/-11.7), P=0.078]. The patients with high-enzymatic activity (ValVal) of COMT gene Val158Met performed significantly better on FIQ than did patients with mid-low enzymatic activity (ValMet and MetMet)[(103.5+/-13.6) vs (100.5+/-11.5), P=0.036]. ADHD children with GG genotype of HTR2A-1438A/G performed significantly better on some aspects of C-WISC test (Full Scale IQ and Verbal Scale IQ) than did children with GA and AA genotypes [FIQ :(106.9+/-10.7) vs (100.7+/-12.3) vs (101.7+/-12.9), P=0.003; VIQ: (110.1+/-10.6) vs (103.5+/-12.1) vs (105.1+/-13.2), P=0.001]. The educational attainment level of the parents was associated with all the aspects of C-WISC test (Full Scale IQ, Verbal Scale IQ, and Performance Scale IQ). The multiple linear regression analysis showed that the genotype of HTR2A-1438A/G had significant correlation with FIQ, VIQ and PIQ; while the educational attainment level of the mother had significant correlation with FIQ and VIQ.

Conclusion: The HTR2A-1438A/G polymorphism and the educational attainment level of the mother were associated with the intelligence of ADHD children in China.

Publication types

  • English Abstract
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Attention Deficit Disorder with Hyperactivity / genetics*
  • Attention Deficit Disorder with Hyperactivity / psychology*
  • Child
  • China
  • Educational Status
  • Female
  • Genetic Association Studies
  • Genotype
  • Humans
  • Intelligence Tests
  • Intelligence*
  • Male
  • Mothers
  • Polymorphism, Genetic
  • Receptor, Serotonin, 5-HT2A / genetics*

Substances

  • Receptor, Serotonin, 5-HT2A