In:
Journal of Child Psychology and Psychiatry, Wiley, Vol. 55, No. 8 ( 2014-08), p. 914-923
Abstract:
Difficulties with performance and brain activity related to attentional orienting (Cue‐P3), cognitive or response preparation (Cue‐ CNV ) and inhibitory response control (Nogo‐P3) during tasks tapping executive functions are familial in ADHD and may represent endophenotypes. The aim of this study was to clarify the impact of dopamine receptor D4 ( DRD 4) and dopamine transporter ( DAT 1) gene polymorphisms on these processes in ADHD and control children. Methods Behavioural and electrophysiological parameters from cued continuous performance tests with low and high attentional load were assessed in boys with ADHD combined type ( N = 94) and controls without family history of ADHD ( N = 31). Both groups were split for the presence of at least one DRD 4 7‐repeat allele and the DAT 1 10‐6 haplotype. Results Children with ADHD showed diminished performance and lower Cue‐P3, CNV and Nogo‐P3 amplitudes. Children with DRD 4 7R showed similar performance problems and lower Cue‐P3 and CNV , but Nogo‐P3 was not reduced. Children with the DAT 1 10‐6 haplotype had no difficulties with performance or Cue‐P3 and CNV , but contrary to expectations increased Nogo‐P3. There were no Genotype by ADHD interactions. Conclusions This study detected specific effects of DRD 4 7R on performance and brain activity related to attentional orienting and response preparation, while DAT 1 10‐6 was associated with elevated brain activity related to inhibitory response control, which potentially compensates increased impulsivity. As these genotype effects were additive to the impact of ADHD , the current results indicate that DRD 4 and DAT 1 polymorphisms are functionally relevant risk factors for ADHD and presumably other disorders sharing these endophenotypes.
Type of Medium:
Online Resource
ISSN:
0021-9630
,
1469-7610
DOI:
10.1111/jcpp.2014.55.issue-8
Language:
English
Publisher:
Wiley
Publication Date:
2014
detail.hit.zdb_id:
1470297-6
SSG:
5,2
