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European Archives of Psychiatry and Clinical Neuroscience

Published in:

01-12-2011 | Original Paper

Neuropsychological endophenotypes in attention-deficit/hyperactivity disorder: a review of genetic association studies

Authors: Oussama Kebir, Ridha Joober

Published in: European Archives of Psychiatry and Clinical Neuroscience | Issue 8/2011

Abstract

As a relatively large body of research has been published up to now, it may be informative to explore whether the use of endophenotypes has produced consistent findings in attention-deficit hyperactivity disorder (ADHD). We reviewed the results of genetic studies investigating associations between putative susceptibility genes for ADHD and neuropsychological traits relevant for this disorder. A PubMed database search identified 47 studies. Most of them (n = 36) examined a single candidate gene, while seven studies examined two or three genes and only four studies examined 10 genes or more. The most investigated genes were DRD4, DAT1, COMT, MAOA, and DBH. Regarding DRD4, association of high reaction time variability with the 7-R allele absence appears to be the most consistent result. Speed of processing, set shifting, and cognitive impulsiveness were less frequently investigated, but seem to be altered in the 7-R allele carriers. Regarding DAT1, majority of studies reported negative results indicating that this gene may have a modulating effect rather than direct influence on cognitive functioning. The other genes were investigated in fewer studies, and the reported findings need to be replicated. The principal methodological issues that could represent confounding factors and may explain conflicting results are discussed.

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Title: Neuropsychological endophenotypes in attention-deficit/hyperactivity disorder: a review of genetic association studies
Authors: Oussama Kebir
Ridha Joober
Publication date: 01-12-2011
Publisher: Springer-Verlag
Published in: European Archives of Psychiatry and Clinical Neuroscience / Issue 8/2011
Print ISSN: 0940-1334
Electronic ISSN: 1433-8491
DOI: https://doi.org/10.1007/s00406-011-0207-5

At a glance: The ONWARDS insulin icodec trials

Springer Medicine

Neuropsychological endophenotypes in attention-deficit/hyperactivity disorder: a review of genetic association studies

Abstract

At a glance: The ONWARDS insulin icodec trials

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