The Not-Invented-Here syndrome

I have high expectations of natural science researchers. I assume that their studies will improve over time, and develop methods and experiments that produce reliable evidence to inform us of human conditions. My confidence is often unrealistic. Scientists are people, after all, and have the same foibles as the rest of us. I anticipate that … Continue reading The Not-Invented-Here syndrome

Little evidence for mitochondrial DNA methylation

This 2018 Japanese rodent study used three different techniques to detect mitochondrial DNA methylation: “Whilst 5-methylcytosine (5mC) is a major epigenetic mark in the nuclear DNA in mammals, whether or not mitochondrial DNA (mtDNA) receives 5mC modification remains controversial. We used bisulfite sequencing, McrBC digestion analyses and liquid chromatography mass spectrometry, which are distinctly differing … Continue reading Little evidence for mitochondrial DNA methylation

The epigenetic clock theory of aging

My 400th blog post curates a 2018 US/UK paper by two of the coauthors of Using an epigenetic clock to distinguish cellular aging from senescence. The authors reviewed the current state of epigenetic clock research, and proposed a new theory of aging: “The proposed epigenetic clock theory of ageing views biological ageing as an unintended … Continue reading The epigenetic clock theory of aging

The role of DNMT3a in fear memories

This 2018 Chinese rodent study found: “Elevated Dnmt3a [a DNA methyltransferase] level in the dorsal dentate gyrus (dDG) of hippocampus was associated with the absence of fear renewal in an altered context after extinction training. Overexpression and knockdown of Dnmt3a in the dDG regulated the occurrence of fear renewal in a bi-directional manner. We found … Continue reading The role of DNMT3a in fear memories

The purpose of epigenetic mechanisms

The concluding remarks of this 2018 Chinese review were: “Using heterochromatin as a model, we have reviewed here the mechanisms behind the establishment and maintenance of silent chromatin domains. We conclude that almost every component of the chromatin environment, including DNA elements, RNAs, histones and other chromatin proteins, plays a role in the process of … Continue reading The purpose of epigenetic mechanisms

How well do single-mother rodent studies inform us about human fathers?

Two items before getting to the review: 94% of rodent genera are naturally uniparental; The Rattus and Mus genera used in almost all rodent research aren’t part of the 6% in which fathers also provide offspring care. This 2018 Australian review subject was paternal intergenerational and transgenerational transmission of biological and behavioral phenotypes per this … Continue reading How well do single-mother rodent studies inform us about human fathers?

Maternal obesity causes fetal liver damage

This 2018 US baboon study was on fetal effects from maternal obesity before and during pregnancy: “Approximately 64% of women of childbearing age in the USA [are] overweight or obese..The baboon is a well-characterized animal model sharing many physiological, metabolic, and genetic characteristics with humans allowing direct translation of findings to human pregnancy. Our study … Continue reading Maternal obesity causes fetal liver damage

Viruses target epigenetic processes

This 2018 Colorado review subject was general and specific ways viruses target epigenetic processes: “We describe viral mechanisms and virus–host interactions by which DNA tumor viruses regulate host DNA methylation to evade antiviral immunity. It is well known that most endogenous retroviruses and retrotransposons in the human genome are inactivated by DNA hypermethylation..In addition to … Continue reading Viruses target epigenetic processes

Lysine acetylation is gnarly and dynamic

This 2018 UC San Francisco cell review provided details of lysine acetylation: “Lysine acetylation has moved from being a specialized mark on histones to a critical modification controlling cell fate, proliferation, and metabolism. During the lifetime of a protein there are many points at which an acetyl group may be added to influence function..The dynamic … Continue reading Lysine acetylation is gnarly and dynamic

DNA methylation and childhood adversity

This 2017 Georgia human review covered: “Recent studies, primarily focused on the findings from human studies, to indicate the role of DNA methylation in the associations between childhood adversity and cardiometabolic disease in adulthood. In particular, we focused on DNA methylation modifications in genes regulating the hypothalamus-pituitary-adrenal axis as well as the immune system.” Recommendations … Continue reading DNA methylation and childhood adversity