Epigenetic

Physics, Chemistry, and Molecular biology (PCMb)

Physics, Chemistry, and Molecular biology (PCMb) link ecological variation to ecological adaptations via a model of gene-cell-tissue-organ-organ system complexity that I first presented in 1992. After adding gene activation by pheromones, I co-authored a book that linked the pheromone-controlled physiology of reproduction across species from microbes to man: The Scent of Eros: Mysteries of Odor in Human Sexuality (1995/2002) Since then, others have written books that claimed that pheromones evolved: Pheromones and Animal Behaviour (2003/2014) and one claimed that mammals…

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RNA-directed DNA methylation and RNA-mediated events

Many colleagues and most of my antagonists seem to be unwilling to accept the fact that RNA-directed DNA methylation links the epigenetic landscape to the physical landscape of DNA in the organized genomes of species from microbes to man. Lack of acceptance appears to be due to the fact that they think mutations and natural selection link evolutionary events to biodiversity. There is no model for that, but they refuse to accept the fact that RNA-mediated events link ecological variation…

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Memory of repression and memory of behavior (2)

“Mutations that become so common that they affect more than 1% of a population are called polymorphisms (for example, the human blood types A, B, AB, and O).“ The claim that human blood types are mutations should be supported with experimental evidence of biologically-based cause and effect. Ask your professor, “What evolutionary event linked the mutation to natural selection and the evolution of human blood types? How did nutrient-dependent cell type differentiation become mutation-initiated cell type differentiation, when it is…

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Memory of repression and memory of behavior

H3K27me and PRC2 transmit a memory of repression across generations and during development Reported as: How epigenetic memory is passed through generations: Sperm and eggs transmit memory of gene repression to embryos Date: September 18, 2014 Excerpt: “There are dozens of potential epigenetic markers. In studies that document parent-to-child epigenetic inheritance, it’s not clear what’s being passed on, and understanding it molecularly is very complicated. We have a specific example of epigenetic memory that is passed on, and we can…

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Behavior (2): All responses are RNA-mediated not genetically-determined

Diana Maria Petrosanu also asked: “who was the author of the article that had stolen your ideas?“ I cannot recall claiming that anyone had stolen our ideas or my ideas. See: Behavior: The first response is RNA-mediated not genetically-determined. In subsequent published works, I extended what we detailed about the molecular epigenetics of sex differences in cell types from yeasts to mammals via examples from model organisms of RNA-mediated cell type differentiation in different species. That is why I was…

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Behavior: The first response is RNA-mediated not genetically-determined

Diana Maria Petrosanu asked a question in an Evolutionary Psychology News discussion about Evolution’s Random Paths Lead to One Place. I’ve been very vocal in other discussions that tout ridiculous theories that have been repeatedly refuted by biological facts. My answer to her question might help others to understand the language of RNA-mediated events. That’s why I added details to my representation at Combating Evolution to Fight Disease.  Whether or not the addition to my comments is published or understood…

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Evolutionary heritage or ecological adaptation? Racism versus reality

Jewish Heritage Written in DNA Fully sequenced genomes of more than 100 Ashkenazi people clarify the group’s history and provide a reference for researchers and physicians trying to pinpoint disease-associated genes. By Kate Yandell | September 9, 2014 Excerpt: These results are compatible with those of prior work on mitochondrial DNA (mtDNA), which is passed on maternally. This prior work suggested that Ashkenazi men from the Middle East intermarried with local European women. The Ashkenazi population “hasn’t been likely as…

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Comparing divergent model organisms

Comparative analysis of the transcriptome across distant species Excerpt: Overall, our results underscore the importance of comparing divergent model organisms to human to highlight conserved biological principles (and disentangle them from lineage-specific adaptations). My comment: In the detailed comparisons of divergent model organisms portrayed in Nutrient-dependent/pheromone-controlled adaptive evolution: a model, I underscored what is known about cell type differentiation in species from microbes to man. By placing what is known into the context of nutrient-dependent amino acid substitutions and biodiversity…

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A microRNA-mediated mechanism that is epigenetically inherited

Pregnancy Stress Spans Generations The stressors a female rat experiences during pregnancy can have repercussions for her granddaughters, a study shows. By Anna Azvolinsky | August 7, 2014 Excerpt: “These changes could be the result of a microRNA (miRNA)-mediated mechanism, which may be epigenetically inherited across generations.” My comment:  There is currently no alternative explanation for these changes. However, a model of how nutrient-dependent pheromone-controlled amino acid substitutions link cell type differentiation (e.g., from the epigenetic landscape to the physical landscape of DNA in…

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microRNAs differentiate neuronal cell types

microRNAs: key triggers of neuronal cell fate Excerpt: “In light of the fact that miRNAs have very precise expression patterns depending on the cell type, tissue and/or developmental stage; it is challenging to generalize a single mechanism to regulate their expression and to identify the target genes that each miRNA has during each stage of neurogenesis. Thus, the combination of bioinformatic tools and experimental techniques will help in the study of miRNAs role in early neurogenesis and how they, their…

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