A remarkable finding in recent research in psychopathology is that not every child is equally susceptible to interventions. Research showed that genetic differences, and in particular a... Show moreA remarkable finding in recent research in psychopathology is that not every child is equally susceptible to interventions. Research showed that genetic differences, and in particular a dopamine-related gene, DRD4, predict who will benefit from interventions, and who will not. In the project "What Works for Whom", this theory was tested, on a large-scale, in the field of early literacy. More than 180 schools spread over the Netherlands were involved in the experiments. We tested the hypothesis that children who were carrier of the DRD4 7-repeat allele, were more receptive to digital educational interventions; one program aimed at understanding the alphabetic principle, and the other program included digital storybooks with animated illustrations. Results for the book reading program were in line with the differential susceptibility theory. The carriers of the DRD4 7-repeat allele, about one-third of the children, benefitted extra from digital storybooks and outperformed their non-carrier peers. For non-carriers the digital books added nothing to the experience children already had with book reading in school and at home. For carriers of the DRD4 7-repeat allele the digital storybooks are a new essential in the curriculum in kindergarten. Show less