Epigenetics

In response to our recent item on the mainstreaming of epigenetics, physicist Rob Sheldon writes to say, in connection with the recent studies of the generational epigenetic effects following mass starvation, — It is, of course, refreshing to see epigenetics now making the mainstream publications. What has me in stitches, however, is all the things that are not said: a) that Darwin hated Lamarck because it reintroduced teleology into evolution. Darwin’s whole purpose was to remove teleology and purpose from a discussion of life, thereby destroying theism. Now the reintroduction of epigenetics leaves the Darwinist program in tatters. b) that the Dutch hunger winter of 1944 wasn’t just Germany blockading Holland, it was the Nazi party. That acme of Darwinian Read More ›

From Israel Rosenfield and Edward Ziff, in a discussion sparked by The Deepest Well: Healing the Long-Term Effects of Childhood Adversity (Houghton Mifflin Harcourt, 2018) at New York Review of Books: When the molecular structure of DNA was discovered in 1953, it became dogma in the teaching of biology that DNA and its coded information could not be altered in any way by the environment or a person’s way of life. The environment, it was known, could stimulate the expression of a gene. Having a light shone in one’s eyes or suffering pain, for instance, stimulates the activity of neurons and in doing so changes the activity of genes those neurons contain, producing instructions for making proteins or other molecules Read More ›

From Salk News: “We are taught that our DNA is something stable and unchanging which makes us who we are, but in reality it’s much more dynamic,” says Rusty Gage, a professor in Salk’s Laboratory of Genetics. “It turns out there are genes in your cells that are capable of copying themselves and moving around, which means that, in some ways, your DNA does change.” For at least a decade, scientists have known that most cells in the mammalian brain undergo changes to their DNA that make each neuron, for example, slightly different from its neighbor. Some of these changes are caused by “jumping” genes—officially known as long interspersed nuclear elements (LINEs)—that move from one spot in the genome to Read More ›

From ScienceDaily: In a new PLOS ONE study, scientists from Kyoto University’s Graduate School of Biostudies have shown that certain ‘mechanosensitive’ genes are suppressed when subjected to audible sound. Moreover, these effects vary depending on cell type, where some don’t show any sensitivity. … “One such gene we examined helps in bone formation, and is known to be upregulated with low-intensity ultrasound pulses,” continues Kumeta. “The other genes were associated with wound healing and the extracellular matrix.” Series of cells were placed in an incubator outfitted with a full-range loudspeaker. After several hours of exposure to sounds with specific frequencies, expression levels of the target genes were analysed. The team found that these mechanosensitive genes were suppressed by up to Read More ›

Not your high school science teacher’s evolution. From Genome Web: A Dutch-led team of researchers examined blood samples obtained from individuals whose mothers were pregnant with them during the Dutch Hunger Winter of 1944 to 1945, toward the end of World War II, and from their siblings who were born either before the six-month famine or after, as they report in Science Advances. This cohort of individuals whose mothers were pregnant during the famine has been shown to have higher rates of obesity, dyslipidemia, diabetes, and schizophrenia, the researchers note. More. Carl Zimmer reports at New York Times: “How on earth can your body remember the environment it was exposed to in the womb — and remember that decades later?” Read More ›

From ScienceDaily: An international group of researchers has discovered a new phenomenon that occurs in identical twins: independent of their identical genes, they share an additional level of molecular similarity that influences their biological characteristics. The researchers propose a mechanism to explain the extra level of similarity and show that it is associated with risk of cancer in adulthood. The results appear in the journal Genome Biology. “The characteristics of an individual depend not only on genes inherited from the parents but also on epigenetics, which refers to molecular mechanisms that determine which genes will be turned on or off in different cell types. If we view one’s DNA as the computer hardware, epigenetics is the software that determines what Read More ›

This sort of finding, assuming it holds up, is killing Darwinism. From ScienceDaily: The amount of close and comforting contact between infants and their caregivers can affect children at the molecular level, an effect detectable four years later, according to new research from the University of British Columbia and BC Children’s Hospital Research Institute. The study showed that children who had been more distressed as infants and had received less physical contact had a molecular profile in their cells that was underdeveloped for their age — pointing to the possibility that they were lagging biologically. “In children, we think slower epigenetic aging might indicate an inability to thrive,” said Michael Kobor, a Professor in the UBC Department of Medical Genetics Read More ›

From Laurie Sanders at Science News: Sperm from stressed-out dads can carry that stress from one generation to another. “But one question that really hasn’t been addressed is, ‘How do dad’s experiences actually change his germ cell?’” Jennifer Chan, a neuroendocrinologist at the University of Pennsylvania, said November 13 in Washington, D.C., at the annual meeting of the Society for Neuroscience. Now, from a study in mice, Chan and her colleagues have some answers, and even hints at ways to stop this stress inheritance. More. Humans have similar structures to mice. Serious findings might explain a lot. How about, growing personal anxiety in the face of reduced external threats? Remember when Darwinians were ridiculing the idea of inheritance of acquired characteristics? Read More ›

Some seem to be in a tizzy about that, according to Michael Le Page at New Scientist: We’ve found out why a Mexican cavefish has no eyes – and the surprising answer is likely to be seized upon by those who think the standard view of evolution needs revising. … It was assumed that these fish became blind because mutations disabled key genes involved in eye development. This has been shown to be the case for some other underground species that have lost their eyes. But Aniket Gore of the US’s National Institute of Child Health and Human Development and colleagues haven’t found any disabling changes in the DNA sequences of eye development genes in the cavefish. Instead, the genes Read More ›

From Lorena Infante Lara at The Smithsonian: But we’re finding out that our DNA isn’t always set in stone. Now, a team of researchers from Northwestern University led by anthropology professor Thom McDade have shown that DNA can also be modified by your environment during childhood. What’s more, the authors conclude in the journal Proceedings of the National Academy of Sciences, those modifications can affect how or when you develop certain illnesses during adulthood. Their investigation followed more than 500 children in the Philippines and found that certain childhood situations can create modifications in genes associated with inflammation, which affects how prone we are to suffer from certain illnesses. Specifically, these factors included socioeconomic status, the prolonged absence of a Read More ›

From Sarah Laskow at Atlas Obscura: Of the possible plant talents that have gone under-recognized, memory is one of the most intriguing. Some plants live their whole lives in one season, while others grow for hundreds of years. Either way, it has not been obvious to us that any of them hold on to past events in ways that change how they react to new challenges. But biologists have shown that certain plants in certain situations can store information about their experiences and use that information to guide how they grow, develop, or behave. Functionally, at least, they appear to be creating memories. How, when, and why they form these memories might help scientists train plants to face the challenges—poor Read More ›

From Shawna Williams at the Scientist: There’s potentially more than one way to deal with stuborn viruses like HSV using epigenetic drugs. While no epigenetics-based antivirals are yet on the market, clinical trials are underway to test the use of chromatin-opening cancer drugs in combination with conventional antiretroviral therapies for HIV, and researchers such as Kristie and Bloom are working to better understand how viruses take advantage of hosts’ epigenomes—and how they might be stopped. The potential for manipulating the latent virus to flush it out of hiding makes epigenetic drugs an appealing strategy for researchers looking for a functional cure for HIV, says virologist Melanie Ott of the Gladstone Institutes. Current antiretroviral therapies effectively control the infection, but if Read More ›

From Ashley Yeager at the Scientist: A study of five far-flung human populations gives clues to adaptations to environmental pressures. The results revealed a strong link between population-specific DNA methylation, mRNA levels, and genotypes. However, the CpG sites where methylation occurred that had the highest degree of population specificity were more strongly associated with a local variation in a single nucleotide (SNP) compared with the association of mRNA levels with local SNPs. Population-specific DNA methylation patterns are therefore explained better by local genetic variants than population-specific expression levels, the team says. Because the DNA methylation variation appears to be under genetic control, it could greatly affect human adaptability. Fraser notes, however, that the consequences of methylation still aren’t clear. “It Read More ›

From ScienceDaily: Epigenetics may explain how Darwin’s finches respond to rapid environmental changes, according to new research published in the open access journal BMC Evolutionary Biology. By studying rural and urban populations of two species of Darwin’s finches on the Galapagos Islands, researchers were able to show that while there was very little genetic variation, there were substantial epigenetic differences that could be related to environmental differences resulting from urbanization. Sabrina McNew, PhD student at the University of Utah and lead author of the study said: “Urbanization of the Galapagos has happened relatively recently, so this is a good opportunity to study how animals respond to rapid environmental change.” … Genetic analysis of the birds revealed very little differences in Read More ›

From ScienceDaily: Scientists reveal that a fault in the process that copies DNA during cell division can cause epigenetic changes that may be inherited for up-to five generations. They also identified the cause of these epigenetic changes, which is related to the loss of a molecular mechanism in charge of silencing genes. Their results, which will be published in Science Advances on 16 August, will change the way we think about the impact of replication stress in cancer and during embryonic development, as well as its inter-generational inheritance. Paper. (public access) – A. Klosin, K. Reis, C. Hidalgo-Carcedo, E. Casas, T. Vavouri, B. Lehner. Impaired DNA replication derepresses chromatin and generates a transgenerational inherited epigenetic memory. Science Advances, 2017 DOI: Read More ›