Further dissection of a genomic locus associated with behavioral activity in the Wistar-Kyoto hyperactive rat, an animal model of hyperkinesis

• Published in: Molecular psychiatry Vol. 8; no. 3; pp. 348 - 352
• Main Authors: MOISAN, M-P, LLAMAS, B, COOK, M. N, MORMEDE, P
• Format: Journal Article
• Language: English
• Published: Basingstoke Nature Publishing Group 01-01-2003
• Subjects: Age; Animal models; Animals; Attention Deficit Disorder with Hyperactivity - genetics; Attention deficit disorders. Hyperactivity; Attention deficit hyperactivity disorder; Behavior; Behavior, Animal - physiology; Biological and medical sciences; Child clinical studies; Chromosome 8; Chromosomes; Chromosomes, Mammalian; Disease Models, Animal; Dissection; Exploratory behavior; Exploratory Behavior - physiology; Female; Gene mapping; Genetic analysis; Genetic markers; Genomes; Genomics; Hyperactivity; Hyperkinesis - genetics; Life Sciences; Lod Score; Male; Medical sciences; Motor Activity - physiology; Psychology. Psychoanalysis. Psychiatry; Psychopathology. Psychiatry; Quantitative trait loci; Rats; Rats, Inbred WKY - genetics; Norway; Vertebrata; Mammalia; Linkage; Rat; Hyperactivity; Animal; Rodentia; Exploration; Genetics; Experimental study; Comparative study; Polymorphism; RAT; GENETIQUE
• ISSN: 1359-4184; 1476-5578
• DOI: 10.1038/sj.mp.4001234

Molecular genetic studies of attention-deficit hyperactivity disorder (ADHD) are a major focus of current research since this syndrome has been shown to be highly heritable.(1) Our approach has been to search for quantitative trait loci (QTL) in a genetic animal model of hyperkinesis, the Wistar-Kyoto hyperactive (WKHA) rat, by a whole-genome scan analysis. In a previous article, we reported the detection of a major QTL associated with behavioral activity in an F2 cross between WKHA and Wistar-Kyoto (WKY) rat strains.(2) Here, we extend our analysis of this cross by adding new genetic markers, now defining a 10 cM interval on rat chromosome 8 associated with ambulatory and exploratory activities. Then we present a replication of this QTL detection, at least for exploratory activity, by a new genetic mapping analysis of an activity QTL in an F2 cross between the WKHA and Brown Norway (BN) rat strains. Overall, the results provide compelling evidence for the presence of gene(s) influencing activity at this locus. The QTL interval has been refined such that the human orthologous region could be defined and tested in human populations for association with ADHD. Ultimately, the improved dissection of this genomic locus should allow the identification of the causal genes.