Title: Prenatal parenting, newborn methylation and child development
Speaker: Marinus H. van IJzendoorn
Time and Location: Friday, Dec 12, 12:00pm, Committee Room 3 (Town Hall).
“Prenatal parenting” seems a contradictio in terminis. In humans however parenting starts way before child birth. Intra-uterine conditions are crucial for the development of the fetus and determine whether the newborn experiences a head start or is already delayed in its neurobiological and psychological development. This is not unlike pre-birth development in rodents as Michael Meaney and his team have documented in detail. Quite some evidence shows that prenatal conditions indeed are associated with later psychosocial and cognitive development.
But how prenatal parenting --for better and for worse—affects the child’s development after birth still is a puzzle to be solved. Epigenetic changes, in particular changes in methylation might be an important piece of this puzzle. The Dutch Hunger Winter Study provided some insight in the profound epigenetic programming taking place in the first trimester after conception when conception took place in the most severe period of famine. In Generation R, a cohort study following 10,000 Rotterdam families from mother’s pregnancy into child’s puberty, we measured several prenatal maternal behaviors, problems and stress factors that might influence methylation patterns assessed in cord blood of the newborn. Epigenome-wide analyses as well as analyses targeting candidate loci may shed some light on prenatal parenting leaving its marks on the neurobiology of the newborn.
My primary research focus has been parenting and its influence on children’s development. In the genomic era when many question whether parenting really matters at all, I have shown that family matters indeedusing not only observational and neurobiological methods, but also experimental parent-training and interventions, as well as meta-analyses that generated new ideas. For example, the Leiden team was the first to demonstrate genetic differential susceptibility in a longitudinal study on parenting and externalizing symptoms (Developmental Psychobiology, 2006), which revived the theory of differential susceptibility making it one of the most innovative and fruitful paradigms in developmental psychology and psychopathology worldwide. Moreover, we were the first to experimentally test the theory of differential susceptibility with a focus on temperamental and genetic factors, extending GxE research to the study of parenting, discovering that contextual factors influence some parents more than others, in a for-better-and-for-worse fashion, depending on their genetic make up (Genes, Brain and Behavior, 2008). Several meta-analyses supported the role of candidate genes as markers of differential susceptibility, emphasizing the interplay of genes and environment in shaping child development. My most important challenge for the near future is experimental work showing susceptibility to the environment, for better and for worse, within the same individual, taking a broader (epi-)genetic perspective and studying mediating mechanisms of differential susceptibility.