Infant DNA methylation and caregiving

This 2019 US human study attempted to replicate findings of animal studies that associated caregiver behavior with infant DNA methylation of the glucocorticoid receptor gene:

“Greater levels of maternal responsiveness and appropriate touch were related to less DNA methylation of specific regions in NR3c1 exon 1F, but only for females. There was no association with maternal responsiveness and appropriate touch or DNA methylation of NR3c1 exon 1F on prestress cortisol or cortisol reactivity. Our results are discussed in relation to programming models that implicate maternal care as an important factor in programing infant stress reactivity.”


The study had many undisclosed and a few disclosed limitations, one of which was:

“Our free-play session, while consistent with the length of free-play sessions in other studies, was short (5 min). It is unclear whether a longer length of time would have yielded significant different maternal responsiveness and appropriate touch data.”

The final sentence showed the study’s purpose was other than discovering factual evidence:

“Following replication of this work, it could ultimately be used in conjunction with early intervention, or home-visiting programs, to measure the strength of the intervention effect at the epigenetic level.”

https://onlinelibrary.wiley.com/doi/full/10.1002/imhj.21789 “DNA methylation of NR3c1 in infancy: Associations between maternal caregiving and infant sex” (not freely available)

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Burying human transgenerational epigenetic evidence

The poor substitutes for evidence in this 2018 US study guaranteed that human transgenerational epigenetically inherited effects wouldn’t be found in the generations that followed after prenatal diethylstilbestrol (DES) exposure:

“A synthetic, nonsteroidal estrogen, DES was administered to pregnant women under the mistaken belief it would reduce pregnancy complications and losses. From the late 1930s through the early 1970s, DES was given to nearly two million pregnant women in the US alone.

Use of DES in pregnancy was discontinued after a seminal report showed a strong association with vaginal clear cell adenocarcinoma in prenatally exposed women. A recent analysis of the US National Cancer Institute (NCI) DES Combined Cohort Follow-up Study showed elevated relative risks of twelve adverse health outcomes.

We do not have sufficient data concerning the indication for DES in the grandmother to determine whether adverse pregnancy outcomes in the third generation might resemble those of their grandmothers. Fourth generation effects of prenatal exposures in humans have not been reported.”


This study had many elements in common with its wretched cited reference [25] “Transgenerational effects of prenatal exposure to the 1944–45 Dutch famine” which is freely available at https://obgyn.onlinelibrary.wiley.com/doi/full/10.1111/1471-0528.12136.

That study’s Methods section showed:

  1. Its non-statistical data was almost all unverified self-reports by a self-selected sample of the F2 grandchildren, average age 37.
  2. No detailed physical measurements or samples were taken of the F2 grandchildren, or of their F1 parents, or of their F0 grandparents, all of which are required as baselines for any transgenerational epigenetic inheritance findings.
  3. No detailed physical measurements or samples were taken of their F3 children, which is the generation that may provide transgenerational evidence if the previous generations also have detailed physical baselines.

That study’s researchers drew enough participants (360) such that their statistics package allowed them to impute and assume into existence a LOT of data. But the scientific method constrained them to make factual statements of what the evidence actually showed. They admitted:

“In conclusion, we did not find a transgenerational effect of prenatal famine exposure on the health of grandchildren in this study.”


The current study similarly used the faulty methods 1-3 above to produce results such as:

“We do not have sufficient data concerning the indication for DES in the [F0] grandmother to determine whether adverse pregnancy outcomes in the [F2] third generation might resemble those of their grandmothers.

Fourth [F3] generation effects of prenatal exposures in humans have not been reported.

Zero studies of probably more than 10,000,000 F3 great-grandchildren of DES-exposed women just here in the US?

Who is against funding these studies? Who is afraid of what such studies may find?

It’s possible that these studies would have similar findings to The transgenerational impact of Roundup exposure:

The transgenerational [F3] pathologies observed include prostate disease, obesity, kidney disease, ovarian disease, and parturition (birth) abnormalities.

For the current study:

  • What could be expected from a study design that didn’t include F3 women and men, which is the only generation that didn’t have direct DES exposure?
  • What a nonsensical study design to permit NON-evidence like educational level!

Human studies of possible intergenerational and transgenerational epigenetic inheritance are urgently needed. There will be abundant evidence to discover if researchers will take their fields seriously.

https://www.sciencedirect.com/science/article/pii/S0890623818304684 “Reproductive and Hormone-Related Outcomes in Women whose Mothers were Exposed in utero to Diethylstilbestrol (DES): A Report from the US National Cancer Institute DES Third Generation Study” (not freely available)

Hijacking the epigenetic clock paradigm

This 2018 German human study’s last sentence was:

“Additionally we found an association between DNAm [DNA methylation] age acceleration and rLTL [relative leukocyte telomere length], suggesting that this epigenetic clock, at least partially and possibly better than other epigenetic clocks, reflects biological age.”

Statements in the study that contradicted, qualified, and limited the concluding sentence included:

“The epigenetic clock seems to be mostly independent from the mitotic clock as measured by the rLTL.

It could be possible that associations are confounded due to short age ranges or non-continuous age distribution, as displayed in the BASE-II cohort (no participants between the age of 38 and 59 years). [see the below graphic]

The BASE-II is a convenience sample and participants have been shown to be positively selected with respect to education, health and cognition.

Samples in which DNAm age and chronological age differed more than three standard deviations from the mean were excluded (N=19).

While the original publication employed eight CpG sites for DNAm age estimation, we found that one of these sites did not significantly improve chronological age prediction in BASE-II. Thus, we reduced the number of sites considered to seven in the present study and adapted the algorithm to calculate DNAm age.

  • Horvath described a subset of 353 methylation sites predicting an individual’s chronological age with high accuracy..
  • Even though the available methods using more CpG sites to estimate DNAm age predict chronological age with higher accuracy..
  • It is not clear how much of the deviation between chronological age and DNAm age reflects measurement error/low number of methylation sites and which proportion can be attributed to biological age.

Due to the statistical method employed, we encountered a systematic deviation of DNAm age in our dataset.”


Findings that aren’t warranted by the data is an all-too-common problem with published research. This study illustrated how researcher hypothesis-seeking behavior – that disregarded what they knew or should have known – can combine with a statistics package to produce almost any finding.

It reminded me of A skin study that could have benefited from preregistration that made a similar methodological blunder:

The barbell shape of the subjects’ age distribution wouldn’t make sense if the researchers knew they were going to later use the epigenetic clock method.

The researchers did so, although the method’s instructive study noted:

“The standard deviation of age has a strong relationship with age correlation”

and provided further details in “The age correlation in a data set is determined by the standard deviation of age” section.

Didn’t the researchers, their organizations, and their sponsors realize that this study’s problematic design and performance could misdirect readers away from the valid epigenetic clock evidence they referenced? What purposes did it serve for them to publish this study?

https://academic.oup.com/biomedgerontology/advance-article-abstract/doi/10.1093/gerona/gly184/5076188 “Epigenetic clock and relative telomere length represent largely different aspects of aging in the Berlin Aging Study II (BASE-II)” (not freely available)

Going off the rails with the biomarker paradigm

This 2018 US government rodent study used extreme dosages to achieve its directed goals of demonizing nicotine and extolling the biomarker paradigm:

“This study examined whether adolescent nicotine exposure alters adult hippocampus-dependent learning, involving persistent changes in hippocampal DNA methylation and if choline, a dietary methyl donor, would reverse and mitigate these alterations.

Mice were chronically treated with nicotine (12.6mg/kg/day) starting at post-natal day 23 (pre-adolescent), p38 (late adolescent), or p54 (adult) for 12 days followed by a 30-day period during which they consumed either standard chow or chow supplemented with choline (9g/kg).

Our gene expression analyses support this model and point to two particular genes involved in chromatin remodeling, Smarca2 and Bahcc1. Both Smarca2 and Bahcc1 showed a similar inverse correlation pattern between promoter methylation and gene expression.

Our findings support a role for epigenetic modification of hippocampal chromatin remodeling genes in long-term learning deficits induced by adolescent nicotine and their amelioration by dietary choline supplementation.”


Let’s use the average weight of a US adult male – published by the US Centers for Disease Control as 88.8 kg – to compare the study’s dosages with human equivalents:

  1. Nicotine at “12.6mg/kg/day” x 88.8 kg = 1119 mg. The estimated lower limit of a lethal dose of nicotine has been reported as between 500 and 1000 mg!
  2. Choline at “9g/kg” x 88.8 kg = 799 g. The US National Institutes of Health published the Tolerable Upper Intake Levels for Choline as 3.5 g!!

Neither of these dosages are even remotely connected to human realities:

  1. The human-equivalent dosage of nicotine used in this study would probably kill an adult human before the end of 12 days.
  2. What effects would an adult human suffer from exceeding the choline “Tolerable Upper Intake Level” BY 228 TIMES for 30 days?

Isn’t the main purpose of animal studies to help humans? What’s the justification for performing animal studies simply to promote an agenda?


A funding source of this study was National Institute on Drug Abuse (NIDA) Identification of Biomarkers for Nicotine Addiction award (T-DA-1002 MG). Has the biomarker paradigm been institutionalized to the point where research proposals that don’t have biomarkers as goals aren’t funded?

https://www.sciencedirect.com/science/article/pii/S107474271830193X “Choline ameliorates adult learning deficits and reverses epigenetic modification of chromatin remodeling factors related to adolescent nicotine exposure” (not freely available)

A book review of “Neuroepigenetics and Mental Illness”

A 2018 online book “Neuroepigenetics and Mental Illness” was published at https://www.sciencedirect.com/bookseries/progress-in-molecular-biology-and-translational-science/vol/158/suppl/C (not freely available). Three chapters are reviewed here, with an emphasis on human studies:


Actually, I won’t waste my time or your time with what I planned to do. The lack of scientific integrity and ethics displayed by the book’s publisher, editor, and contributors in the below chapter spoke volumes.

How can the information in any other chapter of this book be trusted?


“Chapter Twelve: Transgenerational Epigenetics of Traumatic Stress”

This chapter continued propagating a transgenerational meme that had more to do with extending paradigms than science. The meme is that there are adequately evidenced transgenerational epigenetic inheritance human results.

As I most recently noted in Epigenetic variations in metabolism, there aren’t any published human studies that provide incontrovertible evidence from the F0 great-grandparents, F1 grandparents, F2 parents, and F3 children to confirm definitive transgenerational epigenetic inheritance causes and effects. Researchers urgently need to do this human research, and stop pretending that it’s already been done.

How did the book’s editor overlook what this chapter admitted?

“Literature about the inheritance of the effects of traumatic stress in humans has slowly accumulated in the past decade. However, it remains thin and studies in humans also generally lack clear “cause and effect” association, mechanistic explanations or germline assessment.”

Were the publisher and editor determined to keep the chapter heading and the reviewers determined to add another entry to their CVs in the face of this weasel-wording?

“In conclusion, although less studied from a mechanistic point of view, inter- and possibly transgenerational inheritance of the effects of traumatic stress is supported by empirical evidence in humans.”

See the comments below for one example of the poor substitutes for evidence that propagators of the transgenerational meme use to pronounce human transgenerational epigenetic inheritance a fait accompli. Researchers supporting the meme and its funding pipeline know that not only this one example, but also ALL human transgenerational epigenetic inheritance studies:

“Lack clear “cause and effect” association, mechanistic explanations or germline assessment.”

Lack of scientific integrity is one reason why such human research hasn’t been undertaken with the urgency it deserves. Propagating this meme is unethical, and adversely affects anyone who values evidence-based research.

A disturbance in the paradigm of child abuse

The principal way science advances is through the principle Einstein expressed as:

“No amount of experimentation can ever prove me right; a single experiment can prove me wrong.”

Members of the scientific community and of the public should be satisfied that the scientific process is working well when hypotheses are discarded due to nonconfirming evidence. Researchers should strive to develop evidence that rejects paradigms, and be lauded for their efforts.

The opposite took place with this 2018 commentary on two studies where the evidence didn’t confirm current biases. I curated one of these studies in DNA methylation and childhood adversity.

The commentators’ dismissive tone was set in the opening paragraph:

“Is early exposure to adversity associated with a genetic or an epigenetic signature? At first glance, two articles in this issue -..and the other from Marzi et al., who measured genome-wide DNA methylation in a prospective twin cohort assessed at age 18 – appear to say that it is not.”

The two commentators, one of whom was a coauthor of Manufacturing PTSD evidence with machine learning, went on to protect their territory. Never mind the two studies’ advancement of science that didn’t coincide with the commentators’ vested interests.


My main concern with the study was that although the children had been studied at ages 5, 7, 10, 12, and 18, the parents had never been similarly evaluated! The researchers passed up an opportunity to develop the parents as a F0 generation for understanding possible human transgenerational inherited epigenetic causes and effects.

The study focused on the children’s intergenerational epigenetic effects. However, animal studies have often demonstrated transgenerational effects that skip over the F1 generation children!

For example:

https://ajp.psychiatryonline.org/doi/pdf/10.1176/appi.ajp.2018.18020156 “Considering the Genetic and Epigenetic Signature of Early Adversity Within a Biopsychosocial Framework” (not freely available)

How to hijack science: Ignore its intent and focus on the 0.0001%

This 2018 Belgian review hijacked science to further an agenda:

“We addressed this issue at the LATSIS Symposium ‘Transgenerational Epigenetic Inheritance: Impact for Biology and Society’, in Zürich, 28–30 August 2017, and here provide important arguments why environmental and lifestyle-related exposures in young men should be studied.”

The reviewer DETRACTED from science in the studied area – transgenerational epigenetic inheritance – by ignoring its intent. As shown by A self-referencing study of transgenerational epigenetic inheritance which I also curated today, the purpose of such animal studies is to find the mechanisms in order to help humans.


Putting that study’s graphic into human terms, F3 male great-grandchildren may be adversely affected by their F0 great-grandmothers being poisoned while pregnant with their F1 grandfathers, who – with their F2 fathers – may have also been adversely affected.


What the reviewer asserted without proof:

“The importance of maternal lifestyle, diet and other environmental exposures before and during gestation period is well recognized.”

is NOT TRUE for the studied area.

The evidence disproving this assertion is that NO HUMAN STUDIES scientifically demonstrating causes for transgenerational epigenetic inheritance effects have been published!

EVER!!

There’s a huge gap between “The importance..is well recognized” of anything regarding transgenerational epigenetic inheritance and ZERO human studies.

Why has no one published scientifically adequate human evidence to demonstrate “Transgenerational Epigenetic Inheritance: Impact for Biology and Society” effects on ALL of the F1, F2, and F3 human generations as consequences “of maternal lifestyle, diet and other environmental exposures before and during gestation period?” What are we waiting for?

The reviewer said “young men should be studied” but said nothing about resolving bottlenecks in funding human research of the studied area. Do researchers even have opportunities to make a NON-AGENDA-DRIVEN difference in this field?

With ZERO published human studies, transgenerational epigenetic inheritance research can’t be recharacterized into a female vs. male agenda. The reviewer’s attempt to do so diminished the importance of research into human critical development periods.

This agenda’s viewpoint ignored human correlates of evidence from animal studies like The lifelong impact of maternal postpartum behavior:

“The defect in maternal care induced by gestational stress programs the development of the offspring.”

Will the reviewer’s suggested interventions – such as changing an adult’s lifestyle a long time after their development was altered – somehow make up for what went wrong early in their life, even before they were born?

With the evidence from animal studies such as:

is there any doubt that similar mechanisms may be involved in humans, and that human phenotypes may likewise be intergenerationally and/or transgenerationally transmitted?

The reviewer asserted:

“Studying humans is challenging, because of ethical reasons”

But do “ethical reasons” prohibit non-instigating human studies of stress, the intergenerationally and transgenerationally transmitted effects of which seem to be ubiquitous among humans?

In The Not-Invented-Here syndrome I pointed out another problem that the reviewer’s agenda is less than helpful in resolving:

“How can animal studies like the current study help humans when their models don’t replicate common human conditions? This failure to use more relevant models has follow-on effects such as human intergenerational and transgenerational epigenetic inheritance being denigrated due to insufficient evidence.”


I’ll repeat What is a father’s role in epigenetic inheritance? in closing:

“The review focused on 0.0001% of the prenatal period for what matters with the human male – who he was at the time of a Saturday night drunken copulation – regarding intergenerational and transgenerational epigenetic inheritance of metabolic diseases.

The human female’s role – who she was at conception AND THEN what she does or doesn’t do during the remaining 99.9999% of the prenatal period to accommodate the fetus and prevent further adverse epigenetic effects from being intergenerationally and transgenerationally transmitted – wasn’t discussed.

Who benefits from this agenda’s narrow focus?”

https://academic.oup.com/eep/article/4/2/dvy007/4987171 “POHaD: why we should study future fathers”