Letters: Nature vs. nurture


Your article “DNA Referees” [by Amber Dance, May 3] is very informative about epigenetic influences on gene expression, i.e., the study of how the environment can turn genes “on” and “off.” However, you left out one extremely important part of the environment: a child’s care-taking environment.

The way a child is raised, it turns out, can regulate the expression of genes in the child’s developing brain. In a study published earlier this year by Tallie Z. Baram, at UC Irvine, in the Journal of Neuroscience, Baram identified how sensory stimuli from maternal care can modify the gene that controls a key messenger of stress called corticotrophin-releasing hormone.

There are also many epigenetic studies done using animals. For example, Michael Meaney, working with rats at McGill University, and Stephen Suomi, working with monkeys at the National Institutes of Health, have shown that maternal care influences the regulation of gene expression in a number of genes involved in emotional regulation and social relatedness.

This explains why the way a child is raised early in life can have a lasting impact throughout life.

Regina Pally, M.D.

Santa Monica

The writer is executive co-director of the Center for Reflective Parenting, a nonprofit organization dedicated to strengthening the parent-child relationship (

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