Gene-environment interaction (GxE) has become a hot topic of research, with an exponential increase in interest in this area in the past decade. Consider that PubMed lists only 24 citations for “gene environment interaction” prior to the year 2000, but nearly four times that many in the first half of the year 2010 alone! The projected publications on gene-environment interaction for 2008–2010 are on track to constitute more than 40% of the total number of publications on gene-environment interaction indexed in PubMed. Where does all this interest stem from? It may, in part, reflect a merging of interests from fields that were traditionally at odds with one another. Historically, there was a perception that behavior geneticists focused on genetic influences on behavior at the expense of studying environmental influences and that developmental psychologists focused on environmental influences and largely ignored genetic factors. Although this criticism is not entirely founded on the part of either field, methodological and ideological differences between these respective fields meant that genetic and environmental influences were traditionally studied in isolation. More recently, there has been recognition
