May 30, 2018: This was one of the first blog posts I ever wrote. In the nearly five years since, my views on some aspects have evolved considerably from the positions I express in this post, particularly in regards to the strength of the evidence for transgenerational epigenetic inheritance in humans. These two recent Twitter threads (http://bit.ly/2JjTi6H and http://bit.ly/2skmGQp) demonstrate my updated perception of transgenerational inheritance, in particular that while there is good evidence for it in plants and worms, much of the work on this in humans is so poorly designed & over-interpreted that it isn’t even wrong. Identifying true transgenerational epigenetic inheritance in humans would be difficult enough as it is (because of the time scale involved, we just started measuring these things, etc.) so rigourous experimental design and caution in interpreting the results is even more important.
That said, I still stand behind much of what I write in this post. The description from native people such as the Diné of the connections between mothers and infants and between our environments and our selves (i.e., our outsides and our insides) are mirrored by the nature of these connections being revealed by rigorous work in epigenetics. I also think the differences in ethical orientations commensurate with the identification of these connections are also still relevant and merit consideration.
I recently came across this blog post about this recent article on the discovery of epigenetic alterations in infants delivered through C-sections, and it reminded me of an anthropology class I took as an undergrad. One of the books for the course was Molded in the Image of Changing Woman: Navajo Views on the Human Body and Personhood. This book mentioned that the Navajo believe what both mothers and fathers experience before conception and what the mother experiences during gestation has a physical impact on the development of the baby, especially during critical moments in development.
For example, “the Navajo cultural system dictates that particular parts of the human body…are more susceptible to effect than others, and that the human body is more open to effect at critical times in the life cycle – for example, at birth, at puberty and during pregnancy. Knowledge is evoked by such occasions, as well as by illness or accident, at which times knowledge is transferred” (32).
“Precautions must be taken by all Navajo of childbearing age to prevent exposure to death or events of a traumatic nature. Such exposure can negatively affect the mother during delivery or the child before or after birth, or even prior to conception” (125).
“Illness can also result from a parent’s unavoidable exposure to a dangerous situation, as is illustrated [in the following account]. In this case, harmful effect was transferred to a child through her father’s sperm.” In the account, a contemporary Navajo woman describes a conversation with her mother in which she is explaining fetal alcohol syndrome and other effects of drug use on fetal development, and the mother said “Well, of course! That is the reason you had to have a Squaw Dance, was because when your father was away in Kansas on the railroad, you know, he saw an accident…where a white man was killed right in front of his face. And he came back and made love and created you, and so that particular traumatic experience affected every part of him, even his sperm” (126).
At the time I thought this was just an interesting anthropological observation, but an example of some of the far-fetched things ‘primitive’ people believe (boy, they clearly don’t understand how cause and effect works, huh?). However, when later I encountered these same kinds of references–critical developmental windows, the effects on fetal development of the environmental conditions and stressors of both mothers and fathers and even grandparents, the transgenerational transmission of these effects, and so on–as prominent features in the emerging research in epigenetics, I realized I definitely needed to check myself.
Along these same lines, I also recently encountered a blog post by epigenetics researcher Ben Laufer appropriately titled The Haunting of Fearful Memories Across Generations that discusses just these kinds of issues, including links to other articles on the transgenerational transmission of the effects from environmental conditions, including stress. I also appreciate how other researchers in recent papers on epigenetics can say things like “when food is scarce, children may be born ‘pre-programmed’ to cope with undernourishment,” and how “from an evolutionary point of view [transient transgenerational inheritance] makes sense. Our environment changes and we can move from famine to feast, so our bodies need to be able to adapt,” as if these are surprising and novel insights – which they are in the dogmatic context provided by modern genetics – but that traditional Navajo would say “Well, of course!” In other words, I could cite any number of articles of cutting edge research in epigenetics published in prominent scientific journals, which when rephrased in the appropriate vernacular would be accepted as common knowledge by traditional Navajo. Fascinating.
This juxtaposition of the cutting edge of research in contemporary genetics and the life sciences with ancient indigenous beliefs is extraordinarily compelling to me, and fuels my enduring interest in not only the science of epigenetics, but also the history and the philosophy behind it.
So what do you think? I try and steer away from the ‘New Age’ interpretations of epigenetics as much as I can, but do you know of any other similar examples of ancient indigenous knowledge coinciding with ‘new’ scientific results from epigenetics? What do you think of these coincidences? What do they say about contemporary science?
I am curious to hear what you think. Leave your comments below and I will respond.
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