Epigenetic changes are fairly cool to think about as a Fiction writer, for example;
Epigenetic changes have also been observed to occur in response to environmental exposure—for example, mice given some dietary supplements have epigenetic changes affecting expression of the agouti gene, which affects their fur color, weight, and propensity to develop cancerThe idea of changes in fur color and weight (physical manifestations) because of a epigenetic change, which has been induced by the researcher, and the change being predictable has long reaching possibilities, and certainly helps with the story of Winter's Harvest.
It also appears (without being scientific, but as a fiction writer), these changes in the hippocampus's affect on these epigenetic changes, can be induced by the neuropeptides.
Neuropeptides are small protein-like molecules used by neurons to communicate with each other. They are neuronal signaling molecules, influence the activity of the brain in specific ways and are thus involved in particular brain functions, like analgesia, reward, food intake, learning and memory.
Neuropeptides are expressed and released by neurons, and mediate or modulate neuronal communication by acting on cell surface receptors. The human genome contains about 90 genes that encode precursors of neuropeptides. At present about 100 different peptides are known to be released by different populations of neurons in the mammalian brain. Neurons use many different chemical signals to communicate information, including neurotransmitters, peptides, cannabinoids, and even some gases, like nitric oxide.
Of course, altering the physical description of the human body, for even short amounts of time (or perhaps, especially for short amounts of time), would be in the purely fictional areas of reality.
Rita Rebollo, Beatrice Horard, Benjamin Hubert, Cristina Vieira, Jumping genes and epigenetics: Towards new species, Gene, In Press, Corrected Proof, Available online 25 January 2010, ISSN 0378-1119, DOI: 10.1016/j.gene.2010.01.003.
(http://www.sciencedirect.com/science/article/B6T39-4Y7MM1X-1/2/cd3af5316c22e7ec728046a95e5a6ecf)
Abstract:
Transposable elements (TEs) are responsible for rapid genome remodelling by the creation of new regulatory gene networks and chromosome restructuring. TEs are often regulated by the host through epigenetic systems, but environmental changes can lead to physiological and, therefore, epigenetic stress, which disrupt the tight control of TEs. The resulting TE mobilization drives genome restructuring that may sometimes provide the host with an innovative genetic escape route. We suggest that macroevolution and speciation might therefore originate when the host relaxes its epigenetic control of TEs. To understand the impact of TEs and their importance in host genome evolution, it is essential to study TE epigenetic variation in natural populations. We propose to focus on recent data that demonstrate the correlation between changes in the epigenetic control of TEs in species/populations and genome evolution.
Keywords: Transposable elements; Evolution; Rapid speciation; Natural populations; Epigenetic control
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