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After an exhaustive survey of contemporary epigenetics studies, one researcher has concluded that some of the effects of stress, cancer and other chronic diseases may be passed on to our offspring -- and theirs -- through deep and complicated underlying cellular mechanisms that scientists are just beginning to understand.

Adverse life experiences, particularly those in childhood, contribute to disease morbidity and mortality [1, 2, 3, 4, 5, 6, 7]. There is considerable interest in understanding the mechanisms through which they do so, as it remains unclear how illness becomes apparent decades after the presumed initiating event. Long-standing hypotheses include chronic activation of the hypothalamic-pituitary-adrenal axis [8, 9, 10] and alterations of neuroimmune function [11]. Molecular signatures of stressful life experiences and their relation to disease are therefore of special interest to clarify the causal relationship between signature, disease, and stress.

Pharmacogenomics can play an important role in identifying responders and non-responders to medications, avoiding adverse events, and optimizing drug dose. Drug labeling may contain information on genomic biomarkers and can describe: Drug exposure and clinical response variability Risk for adverse events Genotype-specific dosing Mechanisms of drug action Polymorphic drug target and disposition genes The table below lists FDA-approved drugs with pharmacogenomic information in their labeling. The labeling for some, but not all, of the products includes specific actions to be taken based on the biomarker information. Pharmacogenomic information can appear in different sections of the labeling depending on the actions. For more information, please refer to the appropriate labeling guidance.

"The Inner Life of a Cell, an 3 animation created in NewTek LightWave 3D and Adobe After Effects for Harvard biology students. The animation illustrates unseen molecular mechanisms and the ones they trigger, specifically how white blood cells sense and respond to their surroundings and external stimuli."

This case study presents the story of "Nick," a student who has been assigned the task of writing a research paper describing the fundamentals of chemical bonds and how they relate to human life. When Nick experiences difficulty remembering information about the different types of chemical bonds, he turns to his tutor, Josh, for help. Josh explains orbitals and valence electrons to Nick, and then they together review nonpolar and polar covalent bonds, ionic bonds, and hydrogen bonds. A final practical application exercise requires that students write about how different types of chemical bonds may relate to the development of Alzheimer's disease and to the mechanism of action of potential drug treatments.  The case is presented with PowerPoint slides and is designed to be used with a personal response system ("clickers"), but students can instead record their answers on paper or share them verbally.  The content is appropriate for use in high school and undergraduate introductory chemistry and biology courses.

Bowhead whales (Balaena mysticetus), denizens of Arctic seas, are known to live more than 200 years, yet they show few signs of the age-related ailments that plague other animals, including humans. Even the bowhead's closest cetacean relative, the much smaller minke whale, lives only 50 years. That suggests the larger whales (which have more than 1000 times as many cells as humans) have evolved some special natural mechanisms that protect them against cancer and aging.

Behind the unprecedented Ebola outbreak in West Africa lies a species with an incredible power to overtake its host. Zaire ebolavirus and the family of filoviruses to which it belongs owe their virulence to mechanisms that first disarm the immune response and then dismantle the vascular system.

This integrative case study is based on real events that the author experienced with her ten-year-old daughter. Although the names have been changed, all of the events (symptoms, diagnoses and treatments, types of healthcare professionals) are recorded exactly as they occurred. Both asthma and pneumonia are common in the United States (and globally). Many of the drugs described in the case study are frequently prescribed for a wide variety of ailments. The four "episodes" that constitute the case cover 1) a study of asthma triggers, incidence and treatment; 2) side effects and possible medication errors associated with steroids; 3) causes, diagnosis, treatment and prevention of community-acquired bacterial pneumonia; and 4) the mechanism of action of two different antibiotics. The "epilogue" explores a few larger themes related to healthcare and public health (e.g., continuity of care, drug resistance, asthma prevention programs). The case study could be used in an undergraduate, upper-level, infectious disease, microbiology, public health or physiology course or in a graduate-level health professions program.

Researchers have made dramatic inroads into the study of polygenic and other complex human diseases, due in large part to knowledge of the human genome sequence, the generation of widespread markers of genetic variation, and the development of new technologies that allow investigators to associate disease phenotypes with genetic loci. Although polygenic diseases are more common than single-gene disorders, studies of monogenic diseases provide an invaluable opportunity to learn about underlying molecular mechanisms, thereby contributing a great deal to our understanding of all forms of genetic disease.

A cornerstone of modern biomedical research is the use of mouse models to explore basic pathophysiological mechanisms, evaluate new therapeutic approaches, and make go or no-go decisions to carry new drug candidates forward into clinical trials. Systematic studies evaluating how well murine models mimic human inflammatory diseases are nonexistent. Here, we show that, although acute inflammatory stresses from different etiologies result in highly similar genomic responses in humans, the responses in corresponding mouse models correlate poorly with the human conditions and also, one another.

"Survival of the Fittest: Variations in the Clam Species Clamys sweetus" is a guided inquiry. This series of hands-on activities complements the HHMI DVD Evolution: Constant Change and Common Threads and requires simple materials such as M&Ms, Reese's Pieces, food storage bags, and paper cups. This activity has been designed to engage students in thinking about the mechanism of natural selection by encouraging them to formulate questions that can be answered through scientific investigation, data collection, and pattern recognition.

Epigenetics refers to heritable changes in gene expression caused by non-genetic mechanisms, thus by alterations other than in the DNA sequence. Epigenetic changes can persist throughout an organism's lifetime and be passed on to multiple generations. Site offers 4 part "crash course" in epigenetics

7:00 video: This film is the first of a two part series on the evolution of new genetic information. Here we focus on Point Mutations - the simplest natural mechanisms known to increase the genetic information of a population. Our second film of the series will focus on duplication events - natural mutations that increase the total amount of genetic information of an individual. This film was produced under the guidance of molecular biologist Dr. Nicholas Casewell. http://www.lstmed.ac.uk/about/people/... Point mutations are small, natural edits in the DNA code of an individual. These edits can be passed from parent to child. Because they are mere edits, point mutations usually do not increase the total amount of information in an individual. As new information is gained, old information is lost. Point mutations do, however, increase the total amount of information within a population. In this film you will see several examples of beneficial point mutations which have enhanced a creatures abilities or even given rise to entirely new abilities. The first two examples were directly observed in bacteria by scientists in the lab. The third is a case found in domestic dogs, the last example was discovered in several species of wild animal.

Some 20 percent of cancer-related deaths in the U.S. can be attributed to obesity, making it the number-one preventable cause of cancer death in the country. But with myriad metabolic and inflammatory changes associated with obesity, determining the mechanisms that underlie the obesity-cancer link has proven challenging.

Avida-ED is an award-winning educational application developed at Michigan State University for undergraduate biology courses to help students learn about evolution and scientific method by allowing them to design and perform experiments to test hypotheses about evolutionary mechanisms using evolving digital organisms.

Stress is implicated in increased tumor progression risk and poor survival in cancer patients. A number of recent studies have linked these effects to the promotion of tumor cell dissemination through the bloodstream via stress-induced pathways. Now, a mouse study led by researchers in Australia has revealed the mechanisms by which stress modulates cancer's spread through another transport network open to tumor cells-the lymphatic system.

Researchers in a new study at the University of Edinburgh have honed in on five of 89 independent variations in human genetics that are believed to be responsible for autoimmune conditions, from celiac disease and multiple sclerosis to rheumatoid arthritis and asthma. Understanding how these mechanisms work could help scientists to develop new treatments. The team found that a mutation in the ADAR1 gene causes a defect in an "alarm system" in cells that normally protects the body from viruses and other infections by triggering the body's immune system to fight.

By observing how the cells in the zebrafish's skin responded to injury, the Duke team learned a lot about the skin regeneration process and were surprised by its complexity. They saw that in the hours following a fin amputation, for example, zebrafish regenerated skin through three different mechanisms: the "recruitment" of spare skin cells from other areas, a temporary doubling in size in some pre-existing cells, and the creation of completely new cells.

Taxonomy, the practice of classifying biodiversity, has a venerable history. Although early natural historians did not recognize that the similarities and differences among organisms were consequences of evolutionary mechanisms, they still sought a means to organize biological diversity.

This case study teaches students about allopatric speciation through an investigation of the benthic and limnetic sticklebacks of Paxton Lake, which are among the youngest species on Earth, diverging from each other after the Pleistocene glaciers melted and the Gulf Islands formed. Researchers at the University of British Columbia have carried out a variety of fascinating studies on these hardy little fish. Results from this research (formatted as data sheets included in the teaching notes) are provided to students who design experiments and then compare actual data to investigate why benthic and limnetic sticklebacks seldom interbreed in Paxton Lake. Developed for a first-year biology course for majors organized around the general theme of evolution and the history of life on Earth, this case study is an updated version of another case in the collection, "Something's Fishy in Paxton Lake" (Sharp, 2001). The current version is especially suited for a flipped classroom in which students prepare for class ahead of time with a reading assignment that also involves the viewing of a video by the case authors that introduces the mechanisms of allopatric speciation.