title: The developmental origins of chronic physical aggression: biological pathways triggered by early life adversity.
abstract: Longitudinal epidemiological studies with birth cohorts have shown that physical aggression in humans does not appear suddenly in adolescence as commonly thought. In fact, physically aggressive behaviour is observed as early as 12 months after birth, its frequency peaks around 2-4 years of age and decreases in frequency until early adulthood. However, a minority of children (3-7%) maintain a high frequency of physical aggression from childhood to adolescence and develop serious social adjustment problems during adulthood. Genetic factors and early social experiences, as well as their interaction, have been shown to play an important role in the development of chronic aggressive behaviour. However, the biological mechanisms underlying these associations are just beginning to be uncovered. Recent evidence suggests that epigenetic mechanisms are responsive to adverse environments and could be involved in the development of chronic aggression. Using both gene candidate and genomic approaches, recent studies have identified epigenetic marks, such as DNA methylation alterations in genes involved in the stress response and the serotonin and immune systems to be partly responsible for the long-lasting effects of early adversity. Further longitudinal studies with biological, environmental and behavioural assessments from birth onwards are needed to elucidate the sequence of events that leads to these long-lasting epigenetic marks associated with early adversity and aggression.
authors.affiliation: Department of Translational Research in Psychiatry, Max Planck Institute of Psychiatry, Munich 80804, Germany nadine_provencal@psych.mpg.de.
authors.forename: Nadine
authors.initials: N
authors.lastname: Provençal
authors.affiliation: Ste-Justine Hospital Research Center, Montreal, QC H3T 1C5, Canada Department of Psychology and Psychiatry, Queen's University, Kingston, ON K7L 3N6, Canada Department of Psychiatry, University of Montreal, Montreal, QC H3T 1J4, Canada Department of Psychiatry, McGill University, Montreal, QC H3A 1A1, Canada.
authors.forename: Linda
authors.initials: L
authors.lastname: Booij
authors.affiliation: Ste-Justine Hospital Research Center, Montreal, QC H3T 1C5, Canada Department of Psychology and Pediatrics, University of Montreal, Montreal, QC H2V 2S9, Canada School of Public Health, Physiotherapy and Population Sciences, University College Dublin, Dublin 4, Ireland Institute of Genetic, Neurobiological, and Social Foundations of Child Development, Tomsk State University, Tomsk 634050, Russian Federation.
authors.forename: Richard E
authors.initials: RE
authors.lastname: Tremblay
mesh_terms: D000374:Aggression / Q000502:physiology*; D044127:Epigenesis, Genetic; D048788:Growth and Development; D006801:Humans; D008016:Life Change Events; D015398:Signal Transduction
keywords: Aggression; DNA methylation; Development; Early-life stress; Epigenetic; HPA axis; Immune system; Physical aggression; Serotonin