Assessing the molecular genetics of attention networks.
BACKGROUND
Current efforts to study the genetic underpinnings of higher brain functions have been lacking appropriate phenotypes to describe cognition. One of the problems is that many cognitive concepts for which there is a single word (e.g. attention) have been shown to be related to several anatomical networks. Recently, we have developed an Attention Network Test (ANT) that provides a separate measure for each of three anatomically defined attention networks.


RESULTS
In this study we have measured the efficiency of neural networks related to aspects of attention using the ANT in a population of 200 adult subjects. We then examined genetic polymorphisms in four candidate genes (DRD4, DAT, COMT and MAOA) that have been shown to contribute to the risk of developing various psychiatric disorders where attention is disrupted. We find modest associations of several polymorphisms with the efficiency of executive attention but not with overall performance measures such as reaction time.


CONCLUSIONS
These results suggest that genetic variation may underlie inter-subject variation in the efficiency of executive attention. This study also shows that genetic influences on executive attention may be specific to certain anatomical networks rather than affecting performance in a global or non-specific manner. Lastly, this study further validates the ANT as an endophenotypic assay suitable for assessing how genes influence certain anatomical networks that may be disrupted in various psychiatric disorders.
D000293:Adolescent; D000328:Adult; D000483:Alleles; D001288:Attention / Q000502:physiology*; D002394:Catechol O-Methyltransferase / Q000235:genetics; D003071:Cognition / Q000502:physiology*; D004298:Dopamine / Q000235:genetics / Q000378:metabolism; D050483:Dopamine Plasma Membrane Transport Proteins; D005260:Female; D005787:Gene Frequency; D005820:Genetic Testing; D006801:Humans; D008297:Male; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins / Q000235:genetics; D008875:Middle Aged; D008995:Monoamine Oxidase / Q000235:genetics; D009415:Nerve Net / Q000502:physiology*; D009419:Nerve Tissue Proteins; D009483:Neuropsychological Tests / Q000706:statistics & numerical data; D011930:Reaction Time / Q000502:physiology; D017448:Receptors, Dopamine D2 / Q000235:genetics; D050638:Receptors, Dopamine D4; D012016:Reference Values; D012737:Sex Factors
C493599:DRD4 protein, human; D050483:Dopamine Plasma Membrane Transport Proteins; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins; D017448:Receptors, Dopamine D2; C493214:SLC6A3 protein, human; D050638:Receptors, Dopamine D4; D008995:Monoamine Oxidase; D002394:Catechol O-Methyltransferase; D004298:Dopamine