AVPR1A variant associated with preschoolers' lower altruistic behavior.

The genetic origins of altruism, defined here as a costly act aimed to benefit non-kin individuals, have not been examined in young children. However, previous findings concerning adults pointed at the arginine vasopressin receptor 1A (AVPR1A) gene as a possible candidate. AVPR1A has been associated with a range of behaviors including aggressive, affiliative and altruistic phenotypes, and recently a specific allele (327 bp) of one of its promoter region polymorphisms (RS3) has been singled out in particular. We modeled altruistic behavior in preschoolers using a laboratory-based economic paradigm, a modified dictator game (DG), and tested for association between DG allocations and the RS3 "target allele." Using both population and family-based analyses we show a significant link between lower allocations and the RS3 "target allele," associating it, for the first time, with a lower proclivity toward altruistic behavior in children. This finding helps further the understanding of the intricate mechanisms underlying early altruistic behavior