Gene-environment interactions in psychopathology throughout early childhood: a systematic review.

Up to 20% of children and adolescents worldwide suffer from mental health problems. Epidemiological studies have shown that some of these problems are already present at an early age. The recognition that psychopathology is a result of an interaction between individual experiences and genetic characteristics has led to an increase in the number of studies using a gene-environment approach (GxE). However, to date, there has been no systematic review of GxE studies on psychopathology in the first 6 years of life. Following a literature search and a selection process, 14 studies were identified and most (n=12) of the studies found at least one significant GxE effect. This review provides a systematic characterization of the published GxE studies, providing insights into the neurobiological and environmental determinants involved in the etiology of children's psychopathology. (C) 2015 Wolters Kluwer Health, Inc. All rights reserved.