Another important transgenerational epigenetic inheritance study

This 2019 Washington State University rodent study from Dr. Michael Skinner’s lab found:

“A cascade of epigenetic alterations initiated in the PGCs [primordial germ cells] appears to be required to alter the epigenetic programming during spermatogenesis to modify the sperm epigenome involved in the transgenerational epigenetic inheritance phenomenon.

Following fertilization there is a DNA methylation erasure to generate the stem cells in the early embryo, which then remethylate in a cell type-specific manner. The DNA methylation erasure is thought to, in part, reset deleterious epigenetics in the germline. However, imprinted gene DNA methylation sites and induced transgenerational epimutations appear to be protected from this DNA methylation erasure.

A germline with an altered epigenome has the capacity to alter the early embryo’s stem cell’s epigenome and transcriptome that can subsequently impact the epigenomes and transcriptomes of all derived somatic cells. Therefore, an altered sperm epigenome has the capacity to transmit phenotypes transgenerationally. Experiments have demonstrated that epigenetic inheritance can also be transmitted through the female germline.

Previously, the agricultural fungicide vinclozolin was found to promote the transgenerational inheritance of sperm differential DNA methylation regions (DMRs) termed epimutations that help mediate this epigenetic inheritance. The current study was designed to investigate the developmental origins of the transgenerational DMRs during gametogenesis.

The current study with vinclozolin-induced transgenerational inheritance demonstrates that sperm DMRs also originate during both spermatogenesis and earlier stages of germline development, but at distinct developmental stages. This is a genome-wide analysis of epigenetic programming during gametogenesis for transgenerational sperm epimutations.”


The study’s main hypotheses were:

Following fertilization, the hypothesis is that the transgenerational epimutations modify early embryonic transcriptomes and epigenomes to re-establish the cascade for the next generation.

As the individual develops, all somatic cells have altered epigenomes and transcriptomes to promote disease susceptibility later in life.

Researchers: adopt these hypotheses, and don’t limit your study designs to the F1 children as did:

Don’t stop at the F2 grandchildren like:

Continue studies on to F3 descendants who had no direct exposure to the altering stimulus. Keep in the forefront of your research proposals that there are maybe > 10,000,000 F3 great-grandchildren of DES-exposed women just in the US.

https://www.tandfonline.com/doi/pdf/10.1080/15592294.2019.1614417?needAccess=true “Transgenerational sperm DNA methylation epimutation developmental origins following ancestral vinclozolin exposure”

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The transgenerational impact of Roundup exposure

The latest 2019 Washington State University rodent study from Dr. Michael Skinner’s lab found adverse effects in the grand-offspring and great-grand-offspring following their ancestor’s exposure during pregnancy to the world’s most commonly used herbicide:

“Using a transient exposure of gestating F0 generation female rats found negligible impacts of glyphosate on the directly exposed F0 generation, or F1 generation offspring pathology. In contrast, dramatic increases in pathologies in the F2 generation grand-offspring, and F3 transgenerational great-grand-offspring were observed.

The transgenerational pathologies observed include prostate disease, obesity, kidney disease, ovarian disease, and parturition (birth) abnormalities:

  1. Prostate disease in approximately 30% of F3 generation glyphosate lineage males, a three-fold increase in disease rate over controls.
  2. A transgenerational (F3 generation) obese phenotype was observed in approximately 40% of the glyphosate lineage females and 42% of the glyphosate lineage males.
  3. An increased incidence of kidney disease observed in the F3 generation glyphosate lineage females affecting nearly 40% of females.
  4. A significant increase in ovarian disease observed in the F2 [48% vs. 21% for controls] and F3 [36% vs. 15% for controls] generation glyphosate lineage females.
  5. During the gestation of F2 generation mothers with the F3 generation fetuses, dramatic parturition abnormalities were observed in the glyphosate lineage. The frequency of unsuccessful parturition was 35%. To further investigate the parturition abnormalities an outcross of F3 generation glyphosate lineage males with a wildtype female was performed. There were parturition abnormalities observed with a frequency of 30%.

Classic and current toxicology studies only involve direct exposure of the individual, while impacts on future generations are not assessed. The ability of glyphosate and other environmental toxicants to impact our future generations needs to be considered, and is potentially as important as the direct exposure toxicology done today for risk assessment.”


Why isn’t coverage of this study the top story of the world’s news organizations? Is what’s reported more important than reliable evidence of generational consequences to environmental experiences?

Current toxicology practices are a scientific disgrace:

  • What are the hypotheses of practices that only test effects on somatic cells, that don’t look for generational effects of germ cell modifications?
  • Are they selected for their relative convenience instead of chosen for their efficacy?

Why don’t sponsors fund and researchers perform human studies of transgenerational epigenetic inheritance? For example, from Burying human transgenerational epigenetic evidence:

“From the late 1930s through the early 1970s, DES was given to nearly two million pregnant women in the US alone.

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

Zero studies of maybe > 10,000,000 F3 great-grandchildren of DES-exposed women just here in the US!

There will be abundant human evidence to discover if sponsors and researchers will take their fields seriously.

https://www.nature.com/articles/s41598-019-42860-0.pdf “Assessment of Glyphosate Induced Epigenetic Transgenerational Inheritance of Pathologies and Sperm Epimutations: Generational Toxicology”

Non-emotional memories

This 2019 US review covered memory mechanisms:

“With memory encoding reliant on persistent changes in the properties of synapses, a key question is how can memories be maintained from days to months or a lifetime given molecular turnover? It is likely that positive feedback loops are necessary to persistently maintain the strength of synapses that participate in encoding.

These levels are not isolated, but linked by shared components of feedback loops.”


Despite the review’s exhaustive discussion, the reviewers never came to the point. The word cloud I made of the review’s most frequent thirty words had little to do with why memory occurs.

Why do some stimuli evoke a memory in response? Why are almost all of the stimuli an organism receives not remembered?

Much of the discussion was baseless because it excluded emotion. Many of the citations’ memory findings relied on emotion, though. For example, in the subsection Roles of persistent epigenetic modifications for maintaining LTF [long-term facilitation], LTP [long-term potentiation], and LTM [long-term memory]:

  • Histone acetylation is increased after fear conditioning in the hippocampus and amygdala.
  • Correspondingly, inhibition of histone deacetylase enhances fear conditioning and LTP.
  • Following fear conditioning, histone phosphorylation is also increased.
  • DNA methylation is also up-regulated in the hippocampus and amygdala after fear conditioning, and inhibition of DNA methylation blocks fear LTM.”

http://learnmem.cshlp.org/content/26/5/133.full “How can memories last for days, years, or a lifetime? Proposed mechanisms for maintaining synaptic potentiation and memory”

Why do we believe obvious lies?

Here are two accounts of this weekend’s news from real journalists, neither of whom are fans of the current US president.

Matt Taibbi of Rolling Stone
https://taibbi.substack.com/p/russiagate-is-wmd-times-a-million
“It’s official: Russiagate is this generation’s WMD”

He cited intentional misreporting (lying) multiple times from the New York Times, Washington Post, CNN, Wall Street Journal, MSNBC, Mother Jones; and from NBC, ABC, McClatchy, New Yorker, New York Magazine, Bloomberg, BuzzFeed, Slate, Yahoo, Fortune, Guardian; and from numerous US congressmen and senators. Most of these false stories have still not yet been corrected or retracted.

  • “Recapping: the reporter who introduced Steele to the world (his September 23, 2016 story was the first to reference him as a source), who wrote a book that even he concedes was seen as “validating” the pee tape story, suddenly backtracks and says the whole thing may have been based on a Las Vegas strip act, but it doesn’t matter because Stormy Daniels, etc.
  • When explosive #Russiagate headlines go sideways, the original outlets simply ignore the new development, leaving the “retraction” process to conservative outlets that don’t reach the original audiences.
  • The Russiagate era has so degraded journalism that even once “reputable” outlets are now only about as right as politicians, which is to say barely ever, and then only by accident.
  • Authorities have been lying their faces off to reporters since before electricity! It doesn’t take much investigation to realize the main institutional sources in the Russiagate mess – the security services, mainly – have extensive records of deceiving the media.
  • As noted before, from World War I-era tales of striking union workers being German agents to the “missile gap” that wasn’t (the “gap” was leaked to the press before the Soviets had even one operational ICBM) to the Gulf of Tonkin mess to all the smears of people like Martin Luther King, it’s a wonder newspapers listen to whispers from government sources at all.”


Glenn Greenwald of The Intercept
https://twitter.com/ggreenwald

  1. “Can’t the people who got rich exploiting liberal #Resistance fears by feeding them false conspiracies at least content themselves to their bulging bank accounts from the scam they pulled off & have one day of silence where they don’t try to pretend that they were right all along?
  2. If you’re just going to let stuff like this go – unexamined, unacknowledged, and unaccounted for – don’t expect anyone to be remotely sympathetic to the fact that public trust in big media is nonexistent and politicians benefit by making journalists their enemies.
  3. And just for future reference: documenting the falsehoods, baseless conspiracies, and deceitful narratives being peddled without dissent by the major corporate media isn’t “blogging” or “media criticism.” It’s journalism. It’s reporting. And it’s vital.
  4. Nothing kills journalism worse than cowardly group-think, and it’s worse than ever since they’re congregated in the same places in Brooklyn and the West Coast and petrified of saying anything that makes them unpopular among their peers.
  5. Check every MSNBC personality, CNN law “expert,” liberal-centrist outlets and #Resistance scam artist and see if you see even an iota of self-reflection, humility or admission of massive error.
  6. I wrote this with @GGreenwald in November 2016, warning Russiagate was being used to attack, smear, and censor alternative media. Those blacklisted alternative media ended up being correct about Russiagate – while the corporate media spread actual fake news.
  7. There should be major accountability in the US media and in the intelligence community they united with to drown US political discourse for 2 years straight in unhinged conspiratorial trash, distracting from real issues. That’s what should happen as a first step. But it won’t.”

Statistical inferences vs. biological realities

A 2019 UCLA study introduced a derivative of the epigenetic clock named GrimAge:

“DNAm GrimAge, a linear combination of chronological age, sex, and DNAm-based surrogate biomarkers for seven plasma proteins and smoking pack-years, outperforms all other DNAm-based biomarkers, on a variety of health-related metrics.

An age-adjusted version of DNAm GrimAge, which can be regarded as a new measure of epigenetic age acceleration (AgeAccelGrim), is associated with a host of age-related conditions, lifestyle factors, and clinical biomarkers. Using large scale validation data from three ethnic groups, we demonstrate that AgeAccelGrim stands out among pre-existing epigenetic clocks in terms of its predictive ability for time-to-death, time-to-coronary heart disease, time-to-cancer, its association with computed tomography data for fatty liver/excess fat, and early age at menopause.”

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6366976/ “DNA methylation GrimAge strongly predicts lifespan and healthspan”


A miserable attempt at reporting the study’s findings included angles of superstition, fear-of-the-future, and suspicion-by-spurious-association:

“The research has already captured the attention of the life insurance industry. After all, a solid death date could mean real savings when it comes to pricing policies.

The hope is that if and when legitimate anti-aging drugs are developed, GrimAge could be used to test their effectiveness. In a world with functional anti-aging drugs, “doctors could test [your GrimAge number] and say, ‘You know what, you’re aging too quickly. Take this,'” Horvath said.”

https://onezero.medium.com/a-new-test-predicts-when-youll-die-give-or-take-a-few-years-2d08147c8ea6 “A New Test Predicts When You’ll Die (Give or Take a Few Years)”


A detailed blog post from Josh Mitteldorf provided scientific coverage of the study:

“Methylation sites associated with smoking history predicted how long the person would live more accurately than the smoking history itself. Even stranger, the methylation marks most closely associated with smoking were found to be a powerful indication of future health even when the sample was confined to non-smokers.

The DNAm GrimAge clock was developed in two stages, a correlation of a correlation. Curiously, the indirect computation yields the better result.

Horvath’s finding that secondary methylation indicators are more accurate than the underlying primary indicator from which they were derived is provocative, and calls out for a new understanding.”

https://joshmitteldorf.scienceblog.com/2019/03/05/dnam-grimage-the-newest-methylation-clock “DNAm GrimAge—the Newest Methylation Clock”


When there are logical disconnects in findings like the above, it’s time to examine underlying premises. As noted in Group statistics don’t necessarily describe an individual, an assumption required by statistical analyses is that each measured item in the sample is interchangeable with the next.

This presumption is often false, producing individually inapplicable results. For example, Immune memory vs. immune adaptation included this description of the adaptive immune system:

“To be effective, highly specific immune response requires huge diversity of receptors and antibodies, which is achieved by somatic rearrangement of gene segments. Recombination results in millions of TCR [T cell receptor] and antibody variants able to recognize and neutralize millions of various antigens.”

Standard statistics of millions of T cell receptor and antibody variants won’t represent their individually unique properties. Individual differences are their purpose and benefit to us.

The GrimAge study’s overreach was most apparent in stratifying educational attainment to develop correlations. As mentioned in Does a societal mandate cause DNA methylation? such statistics are poor evidence of each individual’s biological realities.

Neither derivatives of group statistics, nor correlations of correlations, seem to be the techniques needed to understand biological causes of effects. Commentators on the GrimAge study mentioned but glossed over this point:

“It remains a mystery why exactly the epigenetic clocks work, and whether age-related changes in DNA methylation contribute to the cause of aging or are a result of it.”

Immune memory vs. immune adaptation

This 2019 Dutch/German/Romanian perspective aimed for a better understanding of immune systems:

“Based on molecular, immunological, and evolutionary arguments, we propose that innate immune memory is a primitive form of immune memory present in all living organisms, while adaptive immune memory is an advanced form of immune memory representing an evolutionary innovation in vertebrates.

Innate immune responses have the capacity to be trained and thereby exert a new type of immunological memory upon reinfection. The central feature of trained innate immune cells is the ability to mount a qualitatively and quantitatively different transcriptional response when challenged with microbes or danger signals. Evidence supports the convergence of multiple regulatory layers for mediating innate immune memory, including changes in chromatin organization, DNA methylation, and probably non-coding RNAs such as microRNAs and/or long non-coding RNAs.

Two properties of the adaptive immune response are mediated by two fundamentally different types of mechanisms:

  1. The higher magnitude and speed of the response is mediated by epigenetic programming.
  2. The specificity of the response is insured by gene recombination of TCR [T cell receptor] and BCR [B cell receptor] and clonal expansion of specific cell subpopulations upon antigen recognition.

To be effective, highly specific immune response requires huge diversity of receptors and antibodies, which is achieved by somatic rearrangement of gene segments. Recombination results in millions of TCR and antibody variants able to recognize and neutralize millions of various antigens.”


The paper included speculations such as the “Evidence supports..probably non-coding RNAs” quoted above, and the penultimate sentence:

“One can envision that vaccines that are capable of inducing both forms of immune memory at the same time would be more effective.”

100% factual evidence is preferred. The paper’s overall information can only be as accurate as the paper’s least accurate information.

The lead author coauthored A dietary supplement that trains the innate immune system and a study referenced in Eat your oats.

https://www.sciencedirect.com/science/article/pii/S1931312818306334 “Innate and Adaptive Immune Memory: an Evolutionary Continuum in the Host’s Response to Pathogens” (not freely available)

Our brains are shaped by our early environments

This 2019 McGill paper reviewed human and animal studies on brain-shaping influences from the fetal period through childhood:

“In neonates, regions of the methylome that are highly variable across individuals are explained by the genotype alone in 25 percent of cases. The best explanation for 75 percent of variably methylated regions is the interaction of genotype with different in utero environments.

A meta-analysis including 45,821 individuals with attention-deficit/hyperactivity disorder and 9,207,363 controls suggests that conditions such as preeclampsia, Apgar score lower than 7 at 5 minutes, breech/transverse presentations, and prolapsed/nuchal cord – all of which involve some sort of poor oxygenation during delivery – are significantly associated with attention-deficit/hyperactivity disorder. The dopaminergic system seems to be one of the brain systems most affected by perinatal hypoxia-ischemia.

Exposure to childhood trauma activates the stress response systems and dysregulates serotonin transmission that can adversely impact brain development. Smaller cerebral, cerebellar, prefrontal cortex, and corpus callosum volumes were reported in maltreated young people as well as reduced hippocampal activity.

Environmental enrichment has a series of beneficial effects associated with neuroplasticity mechanisms, increasing hippocampal volume, and enhancing dorsal dentate gyrus-specific differences in gene expression. Environmental enrichment after prenatal stress decreases depressive-like behaviors and fear, and improves cognitive deficits.”


The reviewers presented strong evidence until the Possible Factors for Reversibility section, which ended with the assertion:

“All these positive environmental experiences mentioned in this section could counterbalance the detrimental effects of early life adversities, making individuals resilient to brain alterations and development of later psychopathology.”

The review’s penultimate sentence recognized that research is seldom done on direct treatments of causes:

“The cross-sectional nature of most epigenetic studies and the tissue specificity of the epigenetic changes are still challenges.”

Cross-sectional studies won’t provide definitive data on cause-and-effect relationships.

The question that remains to be examined is: How can humans best address these early-life causes to ameliorate their lifelong effects?

https://onlinelibrary.wiley.com/doi/full/10.1111/dmcn.14182 “Early environmental influences on the development of children’s brain structure and function” (not freely available)