Visual exploratory behaviour in infancy and novelty seeking in adolescence: two developmentally specific phenotypes of DRD4?

Background: The present study was designed to investigate the association between visual exploratory behaviour in early infancy, novelty seeking in adolescence, and the dopamine D4 receptor (DRD4) genotype. Method: Visual attention was measured in 232 three-month-old infants (114 males, 118 females) from a prospective longitudinal study using a habituation-dishabituation paradigm. At age 15 years, the Junior Temperament and Character Inventory (JTCI/12-18) was administered to assess adolescent novelty seeking. DNA was genotyped for the DRD4 exon III polymorphism. Results: Boys with a higher decrement of visual attention during repeated stimulation in infancy displayed significantly higher JTCI novelty seeking at age 15 years. Furthermore, boys carrying the 7r allele of DRD4 exhibited both greater rates of attention decrement in infancy and higher scores on NS in adolescence. In contrast, no association between DRD4, visual attention and novelty seeking was observed in girls. Conclusions: The present investigation provides further evidence supporting a role of DRD4 in novelty seeking during the course of development.