Wednesday, March 5, 2014


Source Article:
Epigenetic Effects In The Womb And Early Years Can Affect A Baby's Health For A Lifetime

Epigenetic Effects In The Womb And Early Years Can Affect A Baby's Health For A Lifetime

"Childhood family experience", especially in the womb and in the early years, becomes "embedded in the biology of the individual and serves to influence health and capacity over the lifespan." A central mechanism of this process is epigenetics, defined as persistent and heritable alterations in genome information that do not involve changes in DNA sequences themselves.

This was the theme of a recent talk at the University of British Columbia in Vancouver, by Professor Michael Meaney of the Departments of Psychiatry, Neurology and Neurosurgery at McGill University in Montréal, Quebec. Professor Meaney is primarily known for his research on stress, maternal care, and gene expression. His research team has "discovered the importance of maternal care in modifying the expression of genes that regulate behavioral responses to stress."

His research has implications for public policy regarding maternal support and its role in human disease prevention and economic health, because "...brain development and function are regulated by the social environment."

Meaney pointed out that:

* The function of genomes is regulated by epigenetic signals that are a product of the social environment.

* Epigenetic signals in the early years and guide the development and function of the brain.

* Epigenetic changes may occur in germ cells and can be transmitted to one's children.

The field of social epigenetics explores the mechanisms by which diverse factors such as family income, parental behaviour, childrearing practices and, environmental toxins exert their effect by altering the expression of our genes. In other words: "The activation of genes is an environmentally regulated effect." Meaney explained further, that "The development of an individual is an active process of adaptation that occurs within a social and economic context".

"Parental care affects the activity of genes in the brain that regulate stress responses, neural development, and reproduction," he said, and added that parenting quality is often a reflection of the quality of the environment. "Neural and endocrine responses to stress" are "defensive adaptations", and people "become more reactive" to the environment and stressors. In that sense, parental signals are a "forecast" to the young about the nature of the environment that they will encounter: will it be nurturing, or dangerous?

In discussing, "Developmental Origins of Adult Diseases", Meaney elaborated that: Abuse, neglect, harsh discipline, and family strife (related to 'the burdens of poverty')" increase stress hormones and may lead to "depression, drug addiction, anxiety, diabetes, obesity, and heart disease." Moreover, poverty tends to increase parental distress, which may lead to lower "cognitive outcomes" for the child. Child abuse is correlated with about half of all suicides.

Environmental influences across the genome during development moderated by specific genotypes. In one study, 25% of the variations across 1,423 regions of genes were explained by genetics while 75% were the result of the interaction of genes and the environment [i.e. adaptations], which were correlated with such factors as birthweight, smoking, the number of children in the family, depression, length of pregnancy, and obesity.

The message was clear: if society truly cares about its children, it will create a healthy environment in which stress, poverty, violence, toxins, inequality and other harmful conditions are reduced to an absolute minimum." -- Peter G. Prontzos