For generations people have marveled at how birds and butterflies know when and where to migrate, how maternal instincts are either passed down or not, and a host of other such multi-generational mysteries that couldn't be explained by Mendelian genetics.
In the past decade or so, the science of epigenetics has been uncovering bits and pieces of the answers to those questions: It’s coded into the DNA, but it’s malleable.
Put another way, it appears DNA has a variety of options that can be turned on and off, creating a myriad of possible outcomes. This is in response to a wide variety of events, some environmental, some emotional, some experiential, and some by chemical exposure.
Do you remember when the earliest “fetal programming” knowledge was introduced to cattle producers a few years back? In brief, the research on cattle, sheep and people showed that sub-par nutrition for the mother during gestation could harm the health of the offspring for life, and the reproductive performance of that generation and possibly the next generation.
This was counter-intuitive to me! I assumed hard times would program in more efficiency. Instead, it set up the population for a decrease.
More recently, science has been further exploring the myriad of ways – not just reproduction – in which genetic programming can be altered. At this point, it looks myriad beyond anything we can ever really control by simple genetic manipulations or mathematical equations. Should that be a surprise to anyone who has been paying attention?
I read an article just yesterday summarizing some of the latest epigenetic research. Named Epigenetic memories are passed down 14 successive generations, game-changing research reveals, the research the article gives us another small window of understanding how complex is any given genome and the coding that controls all lifeforms.
I suggest reading this article yourself, but will share a few of the revelations here:
The authors wrote, “Scientists formerly speculated that epigenetic changes disappear with each new generation during gametogenesis, the formation of sperm and ovum, and after fertilization. However, this theory was first challenged by research published in the journal Science which demonstrated that transient exposure of pregnant rats to the insecticide methoxychlor, an estrogenic compound, or the fungicide vinclozolin, an antiandrogenic compound, resulted in increased incidence of male infertility and decreased sperm production and viability in 90% of the males of four subsequent generations that were tracked.”
So, this one instance suggests chemical exposure may alter reproduction across four generations or more.
Why 14 generations?
The 14 generations mentioned in the article’s title referred to a study on nematode worms. The nematodes were manipulated to harbor a transgene for fluorescent protein, which caused the worms to glow under ultraviolet light when the gene was activated. Low-temperature incubation did not activate the gene to any significant degree, but worms incubated in higher temperatures glowed brightly, and the genetic alteration persisted for 14 generations or more.
In another study, researchers wafted the chemical acetophenone, which has a cherry-like scent, into the chambers of mice while administering electric shocks, conditioning the mice to fear the scent. They said the fear reaction was passed onto two successive generations, which shuddered significantly more in the presence of acetophenone despite never having encountered it compared to descendants of mice that had not received this conditioning.
In the realm of human studies, the authors recalled that gestational exposure to the Dutch Famine during World War II is associated with lower perceived health, as well as higher incidence of cardiovascular disease, hypertension and obesity in offspring. Maternal undernourishment during pregnancy leads to neonatal adiposity, which is a predictor of future obesity in the grandchildren.
The authors also noted the effects of epigenetic influence of trauma on future generations. As just one example, they cited research showing that descendants of people who survived the Holocaust exhibit abnormal stress-hormone profiles, and low cortisol production in particular. Because of their impaired cortisol response and altered stress reactivity, children of Holocaust survivors are often at enhanced risk for post-traumatic stress disorder (PTSD), anxiety and depression, they said. Similar problems apparently occur for children born after “intrauterine exposure to maternal stress in the form of intimate partner violence during pregnancy.”
Therefore the new science suggest trauma to the parent can affect the children and grandchildren, if not more.
In fact, there is now at least one study which shows RNA-mediated transfer of information from somatic to germ cells.
The researchers concluded that sperm cells can act as the final repositories of somatic cell-derived information, which suggests that epigenetic insults to our body cells can be relayed to future generations.
The latest epigenetic information is a serious blow to traditional Mendelian “laws” of genetics. We should not be surprised. When science is actually working, the narrative must change because new research will constantly revise the information available to us.
I liked this summary by the authors, so I’ll share it with you: “This quintessentially underscores that the air we breathe, the food we eat, the thoughts we allow, the toxins to which we are exposed, and the experiences we undergo may persevere in our descendants and remain in our progeny long after we are gone. We must be cognizant of the effects of our actions, as they elicit a ripple effect through the proverbial sands of time.”
All this recalls for me the quote from Deuteronomy 5:8: “You shall not bow down to them or worship them; for I, the Lord your God, am a jealous God, punishing the children for the sin of the parents to the third and fourth generation of those who hate me …” I had always assumed this was referring to the fact children are prone to mimic their parents, and they their parents. Behavior tends to last for generations, and social “scientists” have long told us this is fundamentally a behavioral sequence. Increasingly, the study of genetics and epigenetics is suggesting the scientists in both disciplines were wrong again.
It is my contention that science rarely gives us answers, although it is often preached as a gospel. The problem is that biological system information is too complex to be determined by reductionist experiments and the so-called solutions they engender. But I believe science can give us insights.
Therefore the wise course of action, when one sees new information like this would be to ask whether it matches or fits into your lifetime of observation. If so, then ask yourself if you can tweak this knowledge into your personal database. Can you alter something you do to improve your life, or the life of your cattle? Can changing the way you manage change your cattle? Can changing their feedstuffs change your outcomes?
Life and science should be a constant blending and reordering of the massive database of information we carry in our heads.