DES-exposure descendants and cancer

A 2020 case study to follow up the wretched Burying human transgenerational epigenetic evidence:

“Diethylstilbestrol (DES) has strengthened concepts of endocrine disrupting chemicals (EDCs) and the fetal basis of adult disease. It is well-known that in-utero exposure to DES induces a wide range of reproductive tract abnormalities, with reports of alterations in Müllerian duct development, fertility problems, ectopic pregnancies, miscarriages, premature births and cancers, particularly clear cell adenocarcinoma (CCAC) of the vagina and cervix.

We report for the first time cervical CCAC in an 8-year-old girl whose maternal grandmother was given DES during pregnancy. She underwent fertility-sparing surgery and radiotherapy. No sign of recurrence was detected throughout a 10-year follow-up.

Her maternal grandmother reported six miscarriages and then DES treatment during the entire 9 months of pregnancy with the patient’s mother. The patient’s mother reported the surgical removal of two-thirds of her left ovary at the age of 12 years for a rapidly growing cyst.

In DES grandsons, we and others have reported a high prevalence of hypospadias, particularly with severe phenotypes, as well as several cases of disorders of sex development. In addition, a cohort study of 47,540 women found significantly elevated odds for attention-deficit / hyperactivity disorder in the DES grandchildren, suggesting a role of EDCs in multigenerational neurodevelopmental deficits.”

https://academic.oup.com/humrep/advance-article-abstract/doi/10.1093/humrep/deaa267/5956098 “Diethylstilbestrol exposure during pregnancy with primary clear cell carcinoma of the cervix in an 8-year-old granddaughter: a multigenerational effect of endocrine disruptors?” (not freely available)


Are researchers and physicians prepared for the great-grandchildren, the transgenerational descendants of DES exposure, who had no possible direct exposure to the toxin?

Have they read everything Dr. Michael Skinner at Washington State University coauthored in the past five years, not just the older review this paper cited? Have they paid close attention to his studies where disease symptoms spared the children and grandchildren, and weren’t evidenced until the great-grandchildren?

There will be abundant evidence to discover if researchers and physicians take their fields seriously. As many as 10 million of these great-grandchildren are alive today, just in the US.

Jet fuel exposure causes diseases in the great-grand offspring

This 2020 Washington State University rodent study examined how great-grandmothers’ JP-8 exposures produced diseases in their great-grand offspring:

“Ancestral exposure to environmental influences such as toxicants, abnormal nutrition, and traumatic stress can affect the germline epigenome and promote the epigenetic transgenerational inheritance of adult onset disease in various organisms from plants to humans. Biological mechanisms underlying transgenerational epigenetic inheritance induced by jet fuel exposure are further investigated in the current study.

Genome-wide association studies (GWAS) have found specific genetic mutations associated with human pathologies, however these genetic mutations generally appear in less than 1% of the disease population. In contrast, epimutations (DNA methylation, histone modifications, non-coding RNA, chromatin structure, and RNA methylation alterations) seem to have a higher frequency and appear in more individuals with the diseases. Determining epigenetic biomarkers for these diseases could become especially useful indicators of environmental exposures and disease susceptibility in the human population.

The number of differential methylated regions (DMRs) found in the transgenerational F3 males is between 100 and 500 for each individual pathology. Few DMRs overlap between the different pathologies which supports the possible use of epimutations as biomarkers of disease. Although further studies are required, the lack of a subpopulation of DMRs overlapping with all pathologies suggests that at a more stringent statistical threshold there are not common DMRs among specific diseases.

Although females develop transgenerational disease, insufficient numbers of oocytes can be obtained on individuals to allow epigenetic associations to be assessed. The study only examined male pathology and associated sperm epimutation associations.”

https://www.sciencedirect.com/science/article/pii/S0890623820301982 “Epigenome-wide association study for transgenerational disease sperm epimutation biomarkers following ancestral exposure to jet fuel hydrocarbons”


The only associations these study subjects had with JP-8 were their great-grandmothers’ jet fuel exposures while pregnant with their grandparents. Other environmental toxicants studied by this group that produced similar transgenerationally inherited diseases were DDT, atrazine, and vinclozolin.

Ever think about your great-grandchildren?

Take responsibility for your one precious life – DHEA

This 2020 meta-analysis subject was DHEA:

“Twenty-four qualified trials were included in this meta-analysis. Statistically significant increases in serum IGF-1 levels were found only in participants who were:

  1. Women; or
  2. Supplementing 50 mg/d; or
  3. Undergoing intervention for > 12 weeks; or
  4. Without an underlying comorbidity; or
  5. Over the age of 60 years.

DHEA supplementation led to an overall increase of ~16 ng/ml in serum IGF-1 levels, as well as increases of ~23 [women] and ~20 ng/ml [age > 60]. Diseased and healthy subjects ages ranged from 20 to 72 years old.”

Discussion section explanations of the above:

  1. “Women are more susceptible to biochemical and clinical shifts caused by DHEA supplementation.
  2. The majority of investigations tested DHEA at a dose of 50 mg/d.
  3. The majority of studies were performed for > 12 weeks.
  4. Participants with no comorbidities were also older in many studies.
  5. Older patients have a natural decline in the production of IGF-1 and DHEA.

Additional rigorous RCTs are warranted to better define whether and to what extent changes in IGF-1 levels caused by DHEA supplementation are relevant for health benefits.”

https://www.sciencedirect.com/science/article/abs/pii/S0531556520302977Impact of dehydroepianrosterone (DHEA) supplementation on serum levels of insulin-like growth factor 1 (IGF-1): A dose-response meta-analysis of randomized controlled trials” (not freely available)


More on IGF-1 from The influence of zinc supplementation on IGF-1 levels in humans: A systematic review and meta-analysis which was cited for “Previous studies have demonstrated that IGF-1 levels can be affected by several factors.”

“IGF-1 is a growth factor synthesized in the liver, and elicits a myriad of effects on health due to its participation in the GH-IGF-1 axis, where it:

  • Is involved in tissue homeostasis;
  • Has anti-apoptotic, mitogenic, anti-inflammatory, antioxidant and metabolic actions;
  • Contributes to skeletal muscle plasticity, maintenance of muscle strength and muscle mass;
  • Neural and cardiovascular protection;
  • Development of the skeleton;
  • Possesses insulin-like effects, and
  • Is a key factor in brain, eye and lung development during fetal development.

IGF-1 plays important roles in both growth and development, and its levels vary depending on age, with peaks generally observed in the postnatal period and at puberty. IGF-1 levels influence the release of GH [growth hormone] from the hypophysis [pituitary gland] via a negative feedback loop.

A rapid decrease in IGF-1 levels is registered during the third decade of life. Levels gradually decrease between the third and the eighth decade of life.”


The Group 3 “> 12 weeks” finding was reinforced by perspectives such as:

Group 4 “with no comorbidities” was narrowly defined. All of us have degrees of diseases in progress. Consider aging effects:

  • Aging as a normal disease “Aging and its diseases are inseparable, as these diseases are manifestations of aging. Instead of healthy aging, we could use the terms pre-disease aging or decelerated aging.”
  • Aging as an unintended consequence “Epigenetic ageing begins from very early moments after the embryonic stem cell stage and continues uninterrupted through the entire lifespan. Ageing is an unintended consequence of processes that are necessary for development of the organism and tissue homeostasis thereafter.”
  • Organismal aging and cellular senescence “If we assume that aging already starts before birth, it can be considered simply a developmental stage, required to complete the evolutionary program associated with species-intrinsic biological functions such as reproduction, survival, and selection.”
  • An environmental signaling paradigm of aging “The age-phenotype of a cell or organ depends on its environment and not its history. Organisms, organs, and their cells can be reset to different age-phenotypes depending on their environment.”

These perspectives are less important than what each of us choose to do about our own problems. Take responsibility for your one precious life.

Transgenerational epigenetic inheritance of epimutations

My 600th curation is a 2020 rodent study from Dr. Michael Skinner’s labs at Washington State University:

“Numerous environmental toxicants have been shown to induce the epigenetic transgenerational inheritance of disease and phenotypic variation. Alterations in the germline epigenome are necessary to transmit transgenerational phenotypes.

In previous studies, the pesticide DDT and the agricultural fungicide vinclozolin were shown to promote the transgenerational inheritance of sperm differential DNA methylation regions, non-coding RNAs and histone retention, which are termed epimutations. The current study was designed to investigate the developmental origins of the transgenerational differential histone retention sites (called DHRs) during gametogenesis of the sperm.

In addition to alterations in sperm DNA methylation and ncRNA expression previously identified, the induction of DHRs in the later stages of spermatogenesis also occurs. This novel component of epigenetic programming during spermatogenesis can be environmentally altered and transmitted to subsequent generations.

While the DHR may be consistent and present between the stages of development, the histone modifications may be altered. Several of the core histone retention sites absent in the DHRs had altered histone methylation. This adds a level of complexity to the potential role of histone retention in that it may be not only the retention, but also the alterations in histone epigenetic modifications.

The DHRs had positional associations with genes and the major functional categories were signaling, metabolism and transcription.

In the event the embryo stem cell population has a modified epigenetics and corresponding transcriptome, then all somatic cells derived from the stem cell population will have an altered cascade of epigenetic and gene expression programming to result in adult differentiated cells with altered epigenetics and transcriptomes. Previous observations have demonstrated in older adult human males alterations in histone retention develop and are associated with infertility.

Similar observations have also been provided for the development of differential DNA methylation regions (DMRs) induced by environmental toxicants such as DDT and vinclozolin. Since DHRs have a similar developmental programming, other epigenetic processes such as ncRNA are also anticipated to be similar.”

https://www.sciencedirect.com/science/article/pii/S0012160620301834 “Developmental origins of transgenerational sperm histone retention following ancestral exposures”


This study, like its dozens of predecessors performed year after year by this research facility, provided evidence for mechanisms of epigenetic transgenerational inheritance. The studied F3 generation members were great-grand-offspring, the first generation to have no direct exposure to DDT and vinclozolin.

As pointed out in A compelling review of epigenetic transgenerational inheritance:

“During the 1950s, the entire North American population was exposed to high levels of the pesticide DDT, when the obesity rate was < 5% of the population. Three generations later, the obesity frequency in North America is now ~45% of the population.”

There are varieties of mischaracterizations and hand-waving denials of epigenetically-inherited diseases. People don’t want to hear about and read proof that something we did or experienced disfavored our children, who unwittingly passed resultant problems on to their children, and which furthered on to their children’s children.

Take responsibility for your one precious life – Vitamin D3

Where to start among 6,489 studies and reviews published during the past five years, results from a PubMed search of “dihydroxyvitamin D3.” How about:

“Vitamin D plays a fundamental role in body calcium and phosphorous homeostasis, ensuring proper functioning of the skeletomuscular system. Pleiotropic activities include:

  • Anti-inflammatory and immunomodulatory properties (predominantly downregulation of adaptive and upregulation of innate immunity);
  • An important role in reproduction, pregnancy, placental functions and fetal and child development;
  • Important in neurodevelopment as well as in the functioning of the adult central and peripheral nervous system;
  • Regulation of global metabolic and endocrine homeostasis and the functions of different endocrine organs, as well as in the functioning of the cardiovascular system;
  • Inhibits malignant transformation, tumor progression and has anti-cancer properties on a variety of tumors;
  • Formation of the epidermal barrier and hair cycling; and
  • Ameliorating effects on skin cancer and on proliferative and inflammatory cutaneous diseases.”

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6342654/ “The serum vitamin D metabolome: What we know and what is still to discover”


Or maybe:

“A study in 6,275 American children and adolescents aged 1–21 years showed that 61% were 25-(OH)D3 insufficient and 9% deficient. In adults, up to 40% are 25-(OH)D3 insufficient and 6% deficient.

Once adequate vitamin D values are reached, to further preserve adequate vitamin D levels in adults, the IOM [Institute of Medicine] recommends a daily dose of 600 IU per day, while the Endocrine Society recommends a dose of 600–2000 IU per day (according to the amount of sunlight the individual is exposed to). There seems to be no additional health benefit in doses higher than 4000 IU/day.

Vitamin D supplementation was protective against acute respiratory tract infections in a 25-(OH)D3 deficient population, especially in those receiving daily or weekly supplementation. However, in children this protective effect could not be reproduced.”

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7281985/ “Vitamin D’s Effect on Immune Function”


Not to forget Advanced glycation end products alter steroidogenic gene expression by granulosa cells: an effect partially reversible by vitamin D:

“This study suggests that there is a relationship between AGEs (advanced glycation end products) and their receptors (RAGE and sRAGE) with vitamin D. Understanding the interaction between AGEs and vitamin D in ovarian physiology could lead to a more targeted therapy for the treatment of ovarian dysfunction.”


Or similarities to broccoli sprouts’ main effect of Nrf2 signaling pathway activation:

“1,25(OH)2D3 plays a role in delaying aging by upregulating Nrf2, inhibiting oxidative stress and DNA damage, inactivating p53‐p21 and p16‐Rb signaling pathways, and inhibiting cell senescence and SASP.”

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6516172/ “1,25‐Dihydroxyvitamin D exerts an antiaging role by activation of Nrf2‐antioxidant signaling and inactivation of p16/p53‐senescence signaling”


Why do we insist on giving ourselves non-communicable diseases?

I recently paid $22.53 after tax for a nearly two-year supply:

A better use of one’s money would be..?

My June 2020 serum 25-OH Vitamin D measurement was 76 on a scale of 0 to 100 from taking a total of 3,400 IU daily. It’s fat-soluble, so I take it along with 1 gram flax oil each time.

Take responsibility for your own one precious life.

Aging as an unintended consequence

The coauthors of 2018’s The epigenetic clock theory of aging reviewed progress that’s been made todate in understanding epigenetic clock mechanisms.

1. Proven DNA methylation features of epigenetic clocks:

  1. “Methylation of cytosines is undoubtedly a binary event.
  2. The increase in epigenetic age is contributed by changes of methylation profiles in a very small percent of cells in a population.
  3. The clock ticks extremely fast in early post-natal years and much slower after puberty.
  4. Clock CpGs have specific locations in the genome.
  5. It applies to prenatal biological samples and embryonic stem cells.

While consistency with all the five attributes does not guarantee veracity of a model, inconsistency with any one will signal the unlikely validity of a hypothesis.”

2. Regarding what epigenetic clocks don’t measure:

“The effects of

  • Telomere maintenance,
  • Cellular senescence,
  • DNA damage signaling,
  • Terminal differentiation and
  • Cellular proliferation

have all been tested and found to be unrelated to epigenetic ageing.”

3. Regarding cyclical features:

Both the epigenetic and circadian clocks are present in all cells of the body, but their ticking rates are regulated. Both these clocks lose synchronicity when cells are isolated from tissues and grown in vitro.

These similarities compel one to ponder potential links between them.”

This was among the points that Linear thinking about biological age clocks missed.

4. The reviewers discussed 3 of the 5 treatment elements in Reversal of aging and immunosenescent trends:

“It is not known at this stage whether the rejuvenating effect is mediated through the regeneration of the thymus or a direct effect of the treatment modality on the body. Also, it is not known if the effect is mediated by all three compounds or one or two of them.

What we know at this stage does not allow the formation of general principles regarding the impact of hormones on epigenetic age, but their involvement in development and maintenance of the body argue that they do indeed have a very significant impact on the epigenetic clock.”

Not sure why they omitted 3000 IU vitamin D and 50 mg zinc, especially since:

“It is not known if the effect is mediated by all three [five] compounds or one or two of them.”

5. They touched on the specialty of Aging as a disease researchers with:

“Muscle stem cells isolated from mice were epigenetically much younger independently of the ages of the tissue / animal from which they were derived.

The proliferation and differentiation of muscle stem cells cease upon physical maturation. These activities are initiated in adult muscles only in response to injury.

6. The reviewers agreed with those researchers in the Conclusion:

“Epigenetic ageing begins from very early moments after the embryonic stem cell stage and continues uninterrupted through the entire lifespan. The significance of this is profound as the question of why we age has been attributed to many different things, most commonly to ‘wear-and-tear.’

The ticking of the epigenetic clock from the embryonic state challenges this perspective and supports the notion that ageing is an unintended consequence of processes that are necessary for

  • The development of the organism and
  • Tissue homeostasis thereafter.”


https://journals.sagepub.com/doi/10.1177/1535370220918329 “Current perspectives on the cellular and molecular features of epigenetic ageing” (not freely available)

Do early experiences of hunger affect our behavior, thoughts, and feelings today?

Reposted from five years ago.


A 2015 worldwide human study Hunger promotes acquisition of nonfood objects found that people’s current degree of hungriness affected their propensity to acquire nonfood items.

The researchers admitted that they didn’t demonstrate cause and effect with the five experiments they performed, although the findings had merit. News articles poked good-natured fun at the findings with headlines such as “Why Hungry People Want More Binder Clips.”

The research caught my eye with these statements:

“Hunger’s influence extends beyond food consumption to the acquisition of nonfood items that cannot satisfy the underlying need.

We conclude that a basic biologically based motivation can affect substantively unrelated behaviors that cannot satisfy the motivation.


The concept of the quotes relates to a principle of Dr. Arthur Janov’s Primal Therapy – symbolic satisfaction of needs. Two fundamentals of Primal Therapy:

  1. The physiological impacts of our early unmet needs drive our behavior, thoughts, and feelings.
  2. The painful impacts of our unfulfilled needs impel us to be constantly vigilant for some way to fulfill them.

Corollary principles of Primal Therapy:

  • Our present efforts to fulfill our early unmet needs will seldom be satisfying. It’s too late.
  • We acquire substitutes now for what we really needed back then.
  • Acquiring these symbols of our early unmet needs may – at best – temporarily satisfy derivative needs.

But the symbolic satisfaction of derived needs – the symptoms – never resolves the impacts of early unfulfilled needs – the motivating causes:

  • We repeat the acquisition behavior, and get caught in a circle of acting out our feelings and impulses driven by these conditions.
  • The unconscious act-outs become sources of misery both to us and to the people around us.

As this study’s findings showed, there’s every reason for us to want researchers to provide a factual blueprint of causes for our hunger sensation effects, such as “unrelated behaviors that cannot satisfy the motivation.

Hunger research objectives could include answering:

  • What enduring physiological changes occurred as a result of past hunger?
  • How do these changes affect the subjects’ present behaviors, thoughts, and feelings?

Hunger research causal evidence for the effect of why people acquire items that cannot satisfy the underlying needmay include studying where to start the timelines for the impacts of hunger. The impacts potentially go back at least to infancy when we were completely dependent on our caregivers.

Infants can’t get up to go to the refrigerator to satisfy their hunger. All a hungry infant can do is call attention to their need, and feel pain from the deprivation of their need.

Is infancy far back enough, though, to understand the beginnings of potential impacts of hunger?

The epigenetics of perinatal stress

This 2019 McGill review discussed long-lasting effects of perinatal stress:

“Epigenetic processes are involved in embedding the impact of early-life experience in the genome and mediating between social environments and later behavioral phenotypes. Since these phenotypes are apparent a long time after the early experience, the changes in gene expression programming must be stable.

Although loss of methylation in a promoter is necessary for expression, it is not sufficient. Demethylation removes a barrier for expression, but expression might be realized at the right time or context when the needed factors or signals are present.

DNA methylation anticipates future transcriptional response to triggers. Comparing steady-state expression with DNA methylation does not capture the full meaning and scope of the regulatory roles of differential methylation.

A model for epigenetic programming by early life stress:

  1. Perinatal stress perceived by the brain triggers release of glucocorticoids (GC) from the adrenal in the mother prenatally or the newborn postnatally.
  2. GC activate nuclear glucocorticoid receptors across the body, which epigenetically program (demethylate) genes that are targets of GR in brain and white blood cells (WBC).
  3. The demethylation events are insufficient for activation of these genes. A brain specific factor (TF) is required for expression and will activate low expression of the gene in the brain but not in blood.
  4. During adulthood a stressful event transiently triggers a very high level of expression of the GR regulated gene specifically in the brain.

Horizontal arrow, transcription; circles, CpG sites; CH3 in circles, methylated sites; empty circles, unmethylated CpG sites; horizon[t]al curved lines, mRNA.”

Points discussed in the review:

  • “Epigenetic marks are laid down and maintained by enzymes that either add or remove epigenetic modifications and are therefore potentially reversible in contrast to genetic changes.
  • The response to early life stress and maternal behavior is also not limited to the brain and involves at least the immune system as well.
  • The placenta is also impacted by maternal social experience and early life stress.
  • Most studies are limited to peripheral tissues such as saliva and white blood cells, and the relevance to brain physiology and pathology is uncertain.
  • The low absolute differences in methylation seen in most human behavioral EWAS raise questions about their biological significance.

  • Although post-mortem studies examine epigenetic programming in physiologically relevant tissues, they represent only a final and single stage that does not capture the dynamic evolution of environments and epigenetic programming in living humans.”

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6952743/ “The epigenetics of perinatal stress”


Other reviewers try to ignore the times when we were all fetuses and newborns. For example, in the same journal issue was a Boston review of PTSD that didn’t mention anything about the earliest times of human lives! Those reviewers speculated around this obvious gap on their way to being paid by NIH.

Why would researchers ignore perinatal stress events that prime humans for later-life PTSD? Stress generally has a greater impact on fetuses and newborns than even infants, and a greater impact on infants than adults.

Epigenetic inheritance and microRNAs

This 2019 Canadian rodent study found:

“Folic acid (FA) supplementation mitigates sperm miRNA profiles transgenerationally following in utero paternal exposure to POPs [persistent organic pollutants]. Across the F1 – F4 generations, sperm miRNA profiles were less perturbed with POPs + FA compared to sperm from descendants of dams treated with POPs alone..and only in F1 sperm.

The POPs mixture represents the pollutant composition found in Ringed seal blubber of Northern Quebec which is a traditional food of Inuit people in that region.

F0 founder dams were gavaged with the POPs mixture corresponding to 500 µg PCBs/kg body weight or corn oil (CTRL) thrice weekly and were fed the AIN-93G diet containing either 2 mg/kg (1X) or 6 mg/kg (3X) of FA ad libitum. Treatments were only administered to F0 founder dams for 9 weeks in total; 5 weeks before mating to untreated males at postnatal day 90 and until parturition. Subsequent lineages, F1 through F4, were neither exposed to POPs nor 3X FA – instead they received 1X FA diet ad libitum.”


Folic acid’s mechanisms weren’t clear:

“The protective role of FA supplementation in the F1 sperm may be partly explained by its antioxidant activity if the miRNA changes are caused by oxidative stress induced by POPs exposure. If, however, the miRNA changes in POPs exposed sperm are due to an altered methylation capacity or dysregulated nucleotide synthesis or mutations, then the increased availability of methyl groups provided by FA supplementation may mitigate the POPs effect by supporting DNA repair through nucleotide synthesis. Additional studies of the interaction between POPs and FA are required.”

Epigenetic inheritance mechanisms were also unclear:

“It remains puzzling how environmentally perturbed paternal miRNAs can persist across multiple generations. To become heritable, parts of the sperm chromatin must escape reprogramming, leading to the possibility that sperm miRNA profiles are subsequently modified by environmental factors. There are clear examples of sperm DNA methylation that escape reprogramming and histones can be involved.”

The study may have produced more clarity had its design investigated DNA methylation as Epigenetic transgenerational inheritance extends to the great-great-grand offspring did. That study also had an intercross breeding scheme with the populations for the F1 – F3 generations before an outcross for the F4 generation because:

“An intercross within the exposure lineage population (with no sibling or cousin breeding to avoid inbreeding artifacts) provides the optimal phenotypes (i.e. pathology) and germline epigenetic alterations.”

Which breeding scheme do you think would more fairly represent the humans of this study? I’d guess that intercross would – if all Inuits eat Ringed seal blubber and have children with other Inuits.

https://academic.oup.com/eep/article/5/4/dvz024/5677505 “Folic acid supplementation reduces multigenerational sperm miRNA perturbation induced by in utero environmental contaminant exposure”

Using oxytocin receptor gene methylation to pursue an agenda

A pair of 2019 Virginia studies involved human mother/infant subjects:

“We show that OXTRm [oxytocin receptor gene DNA methylation] in infancy and its change is predicted by maternal engagement and reflective of behavioral temperament.”

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6795517 “Epigenetic dynamics in infancy and the impact of maternal engagement”

“Infants with higher OXTRm show enhanced responses to anger and fear and attenuated responses to happiness in right inferior frontal cortex, a region implicated in emotion processing through action-perception coupling.

Infant fNIRS [functional near-infrared spectroscopy] is limited to measuring responses from cerebral cortex. It is unknown whether OXTR is expressed in the cerebral cortex during prenatal and early postnatal human brain development.”

https://www.sciencedirect.com/science/article/pii/S187892931830207X “Epigenetic modification of the oxytocin receptor gene is associated with emotion processing in the infant brain”


Both studies had weak disclosures of limitations on their findings’ relevance and significance. The largest non-disclosed contrary finding was from the 2015 Early-life epigenetic regulation of the oxytocin receptor gene:

These results suggest that:

  • Blood Oxtr DNA methylation may reflect early experience of maternal care, and
  • Oxtr methylation across tissues is highly concordant for specific CpGs, but
  • Inferences across tissues are not supported for individual variation in Oxtr methylation.

That rat study found that blood OXTR methylation of 25 CpG sites couldn’t accurately predict the same 25 CpG sites’ OXTR methylation in each subject’s hippocampus, hypothalamus, and striatum (which includes the nucleus accumbens) brain areas. Without significant effects in these limbic system structures, there couldn’t be any associated behavioral effects.

But CpG site associations and correlations were deemed good in the two current studies because they cited:

“Recent work in prairie voles has found that both brain- and blood-derived OXTRm levels at these sites are negatively associated with gene expression in the brain and highly correlated with each other.”

https://www.sciencedirect.com/science/article/pii/S0306453018306103 “Early nurture epigenetically tunes the oxytocin receptor”

The 2018 prairie vole study – which included several of the same researchers as the two current studies – found four nucleus accumbens CpG sites that had high correlations to humans. Discarding one of these CpG sites allowed their statistics package to make a four-decimal place finding:

“The methylation state of the blood was also associated with the level of transcription in the brain at three of the four CpG sites..whole blood was capable of explaining 94.92% of the variance in Oxtr DNA methylation and 18.20% of the variance in Oxtr expression.”

Few limitations on the prairie vole study findings were disclosed. Like the two current studies, there wasn’t a limitation section that placed research findings into suitable contexts. So readers didn’t know researcher viewpoints on items such as:

  • What additional information showed that 3 of the 30+ million human CpGs accurately predicted specific brain OXTR methylation and expression from saliva OXTR methylation?
  • What additional information demonstrated how “measuring responses from cerebral cortex” although “it is unknown whether OXTR is expressed in the cerebral cortex” provided detailed and dependable estimates of limbic system CpG site OXTR methylation and expression?
  • Was the above 25-CpG study evidence considered?

Further contrast these three studies with a typical, four-point, 285-word limitation section of a study like Prenatal stress heightened adult chronic pain. The word “limit” appeared 6 times in that pain study, 3 times in the current fNIRS study, and 0 times in the current maternal engagement and cited prairie vole studies.

Frank interpretations of one’s own study findings to acknowledge limitations is one way researchers can address items upfront that will be questioned anyway. Such analyses also indicate a goal to advance science.

An out-of-date review of epigenetic transgenerational inheritance

This December 3, 2019, French review title was “Transgenerational Inheritance of Environmentally Induced Epigenetic Alterations during Mammalian Development”:

“We attempt to summarize our current knowledge about the transgenerational inheritance of environmentally induced epigenetic changes. While the idea that information can be inherited between generations independently of the DNA’s nucleotide sequence is not new, the outcome of recent studies provides a mechanistic foundation for the concept.

The systematic resetting of epigenetic marks between generations represents the largest hurdle to conceptualizing epigenetic inheritance. Our understanding of the rates and causes of epimutations remains rudimentary.

Environmental exposure to toxicants could promote changes in germline cells at any developmental stage, with more dramatic effects being observed during embryonic germ cell reprogramming. Epigenetic factors and their heritability should be considered during disease risk assessment.”


The review showed an inexplicable lack of thorough research. 2017 was its latest citation of epigenetic transgenerational inheritance studies from the Washington State University labs of Dr. Michael Skinner. I’ve curated six of the labs’ 2019 studies!

  1. Transgenerational diseases caused by great-grandmother DDT exposure;
  2. Another important transgenerational epigenetic inheritance study;
  3. The transgenerational impact of Roundup exposure;
  4. Epigenetic transgenerational inheritance mechanisms that lead to prostate disease;
  5. A transgenerational view of the rise in obesity; and
  6. Epigenetic transgenerational inheritance extends to the great-great-grand offspring.

This lack led to – among other items – equivocal statements where current definitive evidence could have been cited. The review was submitted to the publisher on October 31, 2019, and the above studies were available.


The publisher provided insight into the peer review process via https://www.mdpi.com/2073-4409/8/12/1559/review_report:

  • Peer reviewer 1: “Taking into account that this is not my main area of expertise..Do the authors really believe in that?”
  • Peer reviewer 2 provided a one-paragraph non-review.
  • Peer reviewer 3: “The authors are missing a large sector of what types of environmental factors can influence methylation and do not acknowledge that other sources exist.”

The authors responded with changes or otherwise addressed peer reviewer comments.

https://www.mdpi.com/2073-4409/8/12/1559/htm “Transgenerational Inheritance of Environmentally Induced Epigenetic Alterations during Mammalian Development”

Prenatal stress heightened adult chronic pain

This 2019 McGill rodent study found:

Prenatal stress exacerbates pain after injury. Analysis of mRNA expression of genes related to epigenetic regulation and stress responses in the frontal cortex and hippocampus, brain structures implicated in chronic pain, showed distinct sex and region-specific patterns of dysregulation.

In general, mRNA expression was most frequently altered in the male hippocampus and effects of prenatal stress were more prevalent than effects of nerve injury. Recent studies investigating chronic pain-related pathology in the hippocampus in humans and in rodent models demonstrate functional abnormalities in the hippocampus, changes in associated behavior, and decreases in adult hippocampal neurogenesis.

The change in expression of epigenetic- and stress-related genes is not a consequence of nerve injury but rather precedes nerve injury, consistent with the hypothesis that it might play a causal role in modulating the phenotypic response to nerve injury. These findings demonstrate the impact of prenatal stress on behavioral sensitivity to a painful injury.

Decreased frontal mRNA expression of BDNF and BDNF IV in male offspring following neuropathic pain or prenatal stress respectively. Relative mRNA expression of other stress-related genes (GR17, FKBP5) and epigenetic-related genes (DNMTs, TETs, HDACs, MBDs, MeCP2) in male offspring.

A drastic decrease in expression of HDAC1 was observed in all groups compared to sham-control animals. CCI: chronic constriction injury.”


The study’s design was similar to the PRS (prenatal restraint stress) model, except that the PRS procedure covered gestational days 11 to 21 (birth):

“Prenatal stress was induced on Embryonic days 13 to 17 by restraining the pregnant dams in transparent cylinder with 5 mm water, under bright light exposure, 3 times per day for 45 min.”

None of the French, Italian, and Swiss PRS studies were cited.

The limitation section included:

  1. “Although our study shows significant changes in expression of epigenetic enzymes, it didn’t examine the impact of these changes on genes that are epigenetically regulated by this machinery or their involvement in intensifying pain responses.
  2. The current study is limited by the focus on changes in gene expression which do not necessarily correlate with changes in protein expression.
  3. Another limitation of this study is the inability to distinguish the direct effects of stress in utero vs. changes in the dam’s maternal behavior due to stress during pregnancy; cross-fostering studies are needed to address this issue.
  4. Functional experiments that involve up and down regulation of epigenetic enzymes in specific brain regions are required to establish a causal role for these processes in chronic pain.”

What do you think about possible human applicability of this study’s “effects of prenatal stress were more prevalent than effects of nerve injury” finding?

Are there any professional frameworks that instruct trainees to recognize that if a person’s mother was stressed while pregnant, their prenatal experiences could cause more prevalent biological and behavioral effects than a recent injury?

https://www.sciencedirect.com/science/article/pii/S0166432819315219 “Prenatal maternal stress is associated with increased sensitivity to neuropathic pain and sex-specific changes in supraspinal mRNA expression of epigenetic- and stress-related genes in adulthood” (not freely available)

A review of fetal adverse events

This 2019 Australian review subject was fetal adversities:

“Adversity during the perinatal period is a significant risk factor for the development of neurodevelopmental disorders long after the causative event. Despite stemming from a variety of causes, perinatal compromise appears to have similar effects on the developing brain, thereby resulting in behavioural disorders of a similar nature.

These behavioural disorders occur in a sex‐dependent manner, with males affected more by externalizing behaviours such as attention deficit hyperactivity disorder (ADHD) and females by internalizing behaviours such as anxiety. The term ‘perinatal compromise’ serves as an umbrella term for intrauterine growth restriction, maternal immune activation, prenatal stress, early life stress, premature birth, placental dysfunction, and perinatal hypoxia.

The above conditions are associated with imbalanced excitatory-inhibitory pathways resulting from reduced GABAergic signalling. Methylation of the GAD1/GAD67 gene, which encodes the key glutamate‐to‐GABA synthesizing enzyme Glutamate Decarboxylase 1, resulting in increased levels of glutamate is one epigenetic mechanism that may account for a tendency towards excitation in disorders such as ADHD.

The posterior cerebellum’s role in higher executive functioning is becoming well established due to its connections with the prefrontal cortex, association cortices, and limbic system. It is now suggested that disruptions to cerebellar development, which can occur due to late gestation compromises such as preterm birth, can have a major impact on the region of the brain to which it projects.

Activation of the maternal hypothalamic-pituitary adrenal (HPA) axis and placental protection. Psychological stress is perceived by the maternal HPA axis, which stimulates cortisol release from the maternal adrenal gland.

High levels of maternal cortisol are normally prevented from reaching the fetus by the 11β-hydroxysteroid dehydrogenase 2 (HSD11B2) enzyme, which converts cortisol to the much less active cortisone. Under conditions of high maternal stress, this protective mechanism can be overwhelmed, with the gene encoding the enzyme becoming methylated, which reduces its expression allowing cortisol to cross the placenta and reach the fetus.”


The reviewers extrapolated many animal study findings to humans, although most of their own work was with guinea pigs. The “suggest” and “may” qualifiers were used often – 22 and 37 times, respectively. More frequent use of the “appears,” “hypothesize,” “propose,” and “possible” terms was justified.

As a result, many reviewed items such as the above graphic and caption should be viewed as hypothetical for humans rather than reflecting solid evidence from quality human studies.

The reviewers focused on the prenatal (before birth) period more than the perinatal (last trimester of pregnancy to one month after birth) period. There were fewer mentions of birth and early infancy adversities.

https://onlinelibrary.wiley.com/doi/abs/10.1111/jne.12814 “Perinatal compromise contributes to programming of GABAergic and Glutamatergic systems leading to long-term effects on offspring behaviour” (not freely available)

Epigenetic transgenerational inheritance extends to the great-great-grand offspring

This 2019 rodent study by the Washington State University labs of Dr. Michael Skinner continued to F4 generation great-great-grand offspring, and demonstrated that epigenetic inheritance mechanisms are similar to imprinted genes:

“Epigenetic transgenerational inheritance potentially impacts disease etiology, phenotypic variation, and evolution. An increasing number of environmental factors from nutrition to toxicants have been shown to promote the epigenetic transgenerational inheritance of disease.

Imprinted genes are a special class of genes since their DNA methylation patterns are unchanged over the generation and are not affected by the methylation erasure occurring early in development. The transgenerational epigenetic alterations in the germline appear to be permanently reprogrammed like imprinted genes, and appear protected from this DNA methylation erasure and reprogramming at fertilization in the subsequent generations. Similar to imprinted genes, the epigenetic transgenerational germline epimutations appear to have a methylation erasure in the primordial germ cells involving an epigenetic molecular memory.

Comparison of the transgenerational F3 generation, with the outcross to the F4 generation through the paternal or maternal lineages, allows an assessment of parent-of-origin transmission of disease or pathology. Observations provided examples of the following:

  1. Pathology that required combined contribution of both paternal and maternal alleles to promote disease [testis and ovarian disease];
  2. Pathology that is derived from the opposite sex allele such as father to daughter [kidney disease] or mother to son [prostate disease];
  3. Pathology that is derived from either parent-of-origin alleles independently [obesity];
  4. Pathology that is transmitted within the same sex, such as maternal to daughter [mammary tumor development]; and
  5. Pathology that is observed only following a specific parent-of-origin outcross [both F4 male obesity and F4 female kidney disease in the vinclozolin lineage].”

The study showed that epigenetically inherited legacies extend to the fifth generation. Do any of us know our ancestors’ medical histories back to our great-great-grandparents?

Will toxicologists take their jobs seriously, catch up to the current science, and investigate possible effects in at least the F3 generation that had no direct toxicant exposure?

https://www.sciencedirect.com/science/article/pii/S0012160619303471 “Epigenetic transgenerational inheritance of parent-of-origin allelic transmission of outcross pathology and sperm epimutations”

Do genes or maternal environments shape fetal brains?

This 2019 Singapore human study used Diffusion Tensor Imaging on 5-to-17-day old infants to find:

“Our findings showed evidence for region-specific effects of genotype and GxE on individual differences in human fetal development of the hippocampus and amygdala. Gene x Environment models outcompeted models containing genotype or environment only, to best explain the majority of measures but some, especially of the amygdaloid microstructure, were best explained by genotype only.

Models including DNA methylation measured in the neonate umbilical cords outcompeted the Gene and Gene x Environment models for the majority of amygdaloid measures and minority of hippocampal measures. The fact that methylation models outcompeted gene x environment models in many instances is compatible with the idea that DNA methylation is a product of GxE.

A genome-wide association study of SNP [single nucleotide polymorphism] interactions with the prenatal environments (GxE) yielded genome wide significance for 13 gene x environment models. The majority (10) explained hippocampal measures in interaction with prenatal maternal mental health and SES [socioeconomic status]. The three genome-wide significant models predicting amygdaloid measures, explained right amygdala volume in interaction with maternal depression.

The transcription factor CUX1 was implicated in the genotypic variation interaction with prenatal maternal health to shape the amygdala. It was also a central node in the subnetworks formed by genes mapping to the CpGs in neonatal umbilical cord DNA methylation data associating with both amygdala and hippocampus structure and substructure.

Our results implicated the glucocorticoid receptor (NR3C1) in population variance of neonatal amygdala structure and microstructure.

Estrogen in the hippocampus affects learning, memory, neurogenesis, synapse density and plasticity. In the brain testosterone is commonly aromatized to estradiol and thus the estrogen receptor mediates not only the effects of estrogen, but also that of testosterone.”

https://onlinelibrary.wiley.com/doi/full/10.1111/gbb.12576 “Neonatal amygdalae and hippocampi are influenced by genotype and prenatal environment, and reflected in the neonatal DNA methylome” (not freely available)