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Background: The dopamine D4 receptor gene (DRD4) has been linked to attention deficit hyperactivity disorder (ADHD) and reading disorders. In this study, we examined whether diminished anticipatory dopamine cell firing - typical of the long variant of the DRD4 allele - is related to emergent and advanced alphabetic skills, and whether executive attention is a mediator between this allele and alphabetic skills. Method: We tested alphabetic skills in a normative sample of 159 children in both kindergarten and Grade 1, and executive attention 1 year earlier. Cheek cells were collected and genomic DNA was isolated from the samples using the Chemagic buccal swab kit on a chemagen Module I workstation. Results: Thirty-seven percent of the children were carriers of at least one DRD4 7-repeat allele. Carriers of the long variant scored lower on alphabetic skills, and executive attention appeared to be a mediator of the relation between characteristics of DRD4 and alphabetic skills in kindergarten and first grade. Conclusion: This study shows how a genetic factor which has been shown to relate to variation in attention and regulatory behavior can explain delays in alphabetic skills. A practical implication is that in many cases early interventions should not only target reading skills, but also support children's engagement in tasks. [ABSTRACT FROM AUTHOR]

In this randomized controlled trial, 312 low-socioeconomic-status children (Mage = 52.9 months, SD = 3.2) from 15 Dutch schools participated. Children in the intervention condition played early literacy games via the intelligent tutoring system Living Letters. Control children played a nonliteracy computer game. At the beginning of each intervention session, children received instruction from computer characters about how to play the game. While playing the game, half of the children in the intervention group received individualized feedback, which included oral corrections and cues from a computer tutor. The other half of the children received no individualized feedback. On average the intervention comprised 11 sessions (approximately 110 min). A main finding was that children's code-related skills increased as a result of the Living Letters program but only when the program included a computer tutor that gave oral feedback to children's correct responses and errors. Children with underdeveloped inhibitory control scored disproportionately low in a computer environment without tutoring. [ABSTRACT FROM AUTHOR]

In this randomized controlled trial, 508 5-year-old kindergarten children participated, of whom 257 were delayed in literacy skills because they belonged to the lowest quartile of a national standard literacy test. We tested the hypothesis that some children are more susceptible to school-entry educational interventions than their peers due to their genetic makeup, and thus whether the dopamine receptor D4 gene moderated intervention effects. Children were randomly assigned to a control condition or one of two interventions involving computer programs tailored to the literacy needs of delayed pupils: Living Letters for alphabetic knowledge and Living Books for text comprehension. Effects of Living Books met the criteria of differential susceptibility. For carriers of the dopamine receptor D4 gene seven-repeat allele (about one-third of the delayed group), the Living Books program was an important addition to the common core curriculum in kindergarten (effect size d = 0.56), whereas the program did not affect the other children (d = –0.09). The same seven-repeat carriers benefited more from Living Letters than did the noncarriers, as reflected in effect sizes of 0.63 and 0.34, respectively, although such differences did not fulfill the statistical criteria for differential susceptibility. The implications of differential susceptibility for education and regarding the crucial question “what works for whom?” are discussed. [ABSTRACT FROM AUTHOR]