You were a complex, small creature that had a pre-birth life in the womb that profoundly influenced your long-term health and behavior: “The quality of life in the womb, our temporary home before we were born, programs our susceptibility to coronary artery disease, stroke, diabetes, obesity and a multitude of other conditions in later life,” writes Dr. Peter W. Nathanielsz in Life in the Womb: The Origin of Health and Disease. [Nathanielsz 1999] Recently, an even wider range of adult-related chronic disorders, including osteoporosis, mood disorders and psychoses, have been intimately linked to pre- and perinatal developmental influences. [Gluckman and Hanson 2004]
Recognizing the role the prenatal environment plays in creating disease forces a reconsideration of genetic determinism. Nathanielsz writes: “There is mounting evidence that programming of lifetime health by the conditions in the womb is equally, if not more important, than our genes in determining how we perform mentally and physically during life. Gene myopia is the term that best describes the current all-pervasive view that our health and destiny throughout life are controlled by our genes alone…In contrast to the relative fatalism of gene myopia, understanding the mechanisms that underlie programming by the quality of life in the womb, we can improve the start in life for our children and their children.”
The programming “mechanisms” Nathanielsz refers to are the epigenetic mechanisms, discussed earlier, by which environmental stimuli regulate gene activity. As Nathanielsz states, parents can improve the prenatal environment. In so doing they act as genetic engineers for their children. The idea that parents can transmit hereditary changes from their life to their children is, of course, a Lamarckian concept that conflicts with Darwinism. Nathanielsz is one of the scientists who are now brave enough to invoke the “L” word for Lamarck: “…the transgenerational passage of characteristics by nongenetic means does occur. Lamarck was right, although transgenerational transmission of acquired characteristics occurs by mechanisms that were unknown in his day.”
The responsiveness of individuals to the environmental conditions perceived by theirs mothers before birth allows them to optimize their genetic and physiologic development as they adapt to the environmental forecast.
Gluckman, P. D. and M. A. Hanson (2004). “Living with the Past: Evolution, Development, and Patterns of Disease.” Science 305: 1733-1736.
Nathanielsz, P. W. (1999). Life In the Womb: The Origin of Health and Disease. Ithaca, NY, Promethean Press.