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Panobinostat is a new type of drug that works by blocking an enzyme responsible for modifying DNA at the epigenetic level. Epigenetics refers to chemical marks on DNA itself or on the protein "spools" called histones that package DNA. These marks influence the activity of genes without changing the underlying sequence, essentially acting as volume knobs for genes. Earlier genomic studies showed that about 80 percent of DIPG tumors carry a mutation that alters a histone protein, resulting in changes to the way DNA is packaged and tagged with those chemical marks. This faulty epigenetic regulation results in activation of growth-promoting genes that should have been turned off, and shutdown of others that should have acted as brakes to cell multiplication. Cancer is the result. Panobinostat appears to work by restoring proper functioning of the cells' chemical tagging system.

A common misconception is that Darwin suggested that something as complex as the eye could not have evolved through natural selection. While the misunderstanding often comes from an incomplete reading of his argument, we have long known that intermediate varieties of eyes (e.g., eyespots, cupped eyes, and complex camera-type eyes) exist in a variety of organisms. Eyes are so common that it was thought that they had evolved independently 40-60 times. More recent molecular work, however, has identified the role of Pax6 genes and their homologs in the formation of eyes during development. The basic information for eye formation appears to have been present in the common ancestor to all bilaterans, and perhaps may be more ancient than that. This interrupted case study examines the history of evidence for eye evolution from Darwin's initial postulates, through evidence of multiple intermediate forms, concluding in an examination of Pax6 homologs. The case is primarily for an introductory biology class but an additional section would be appropriate for upper-level evolution or developmental biology courses.

Why is the North American population of monarch butterflies declining? In 1999, a study published in the journal Nature suggested that a variety of genetically modified corn was killing these iconic butterflies. While it was later shown that the conditions in this study did not mirror those in the field, the results garnered a lot of media attention and many people today still believe that monarchs are being killed by GMOs. This case familiarizes students with the plight of the monarchs, encourages them to think about how to test the hypothesis that a toxin is responsible for their decline, and takes a critical look at several studies that investigated the role of Bt corn in the life cycle of monarchs. This interrupted case takes 60-90 min to complete, requires little to no science background, and can be used to explore the ecology and wildlife management of monarchs; risk assessment, toxicity, and exposure; experimental design, the scientific method, hypothesis, and critical thinking; or the relationship between science, the media and the public.

If you are finding it difficult to understand stem cells, you should know that many other people share your struggle. To make it easier for everyone, we have created a website that covers all you need to know about the topic. With regular updates and a language that speaks clearly, we hope that you will understand the potential of stem cells and how they might play a role in your life or that of someone you know.

The external environment's effects upon genes can influence disease, and some of these effects can be inherited in humans. Studies investigating how environmental factors impact the genetics of an individual's offspring are difficult to design. However, in certain parts of the world in which social systems are highly centralized, environmental information that might have influenced families can be obtained. For example, Swedish scientists recently conducted investigations examining whether nutrition affected the death rate associated with cardiovascular disease and diabetes and whether these effects were passed from parents to their children and grandchildren (Kaati et al., 2002). These researchers estimated how much access individuals had to food by examining records of annual harvests and food prices in Sweden across three generations of families, starting as far back as the 1890s. These researchers found that if a father did not have enough food available to him during a critical period in his development just before puberty, his sons were less likely to die from cardiovascular disease. Remarkably, death related to diabetes increased for children if food was plentiful during this critical period for the paternal grandfather, but it decreased when excess food was available to the father. These findings suggest that diet can cause changes to genes that are passed down though generations by the males in a family, and that these alterations can affect susceptibility to certain diseases. But what are these changes, and how are they remembered? The answers to questions such as these lie in the concept of epigenetics.

Lyme disease, Ebola and malaria all developed in animals before making the leap to infect humans. Predicting when such a 'zoonotic' disease will spark an outbreak remains difficult, but a new study suggests that artificial intelligence could give these efforts a boost. A computer model that incorporates machine learning can pinpoint, with 90% accuracy, rodent species that are known to harbour pathogens that can spread to humans, researchers report this week in the Proceedings of the National Academy of Sciences1. The model also identified more than 150 species that are likely to be disease reservoirs but have yet to be confirmed as such.

When an elementary school teacher calls in sick to work, she finds out that she is not the only one who will be missing school that day.  Children from her fifth grade class have also become ill and parents are calling to report the absences. The concerned principal of the school finds out the fifth grade class had a field trip to one of the local parks the day before. The case shows the areas visited by the class and provides discussion between the principal and a physician that teaches the readers about water quality and EPA standards for bacteria levels in recreational water. The case has an optional lab component that provides the theory for three methods that can be used to conduct microbial water analyses.  Procedures are included for teachers to lead a lab activity to test water to identify which location in the park caused the illness. This case study and accompanying laboratory activity are recommended for an environmental engineering course or a lower level science course.

Biologists estimate that there are about 5 to 100 million species of organisms living on Earth today. Evidence from morphological, biochemical, and gene sequence data suggests that all organisms on Earth are genetically related, and the genealogical relationships of living things can be represented by a vast evolutionary tree, the Tree of Life. The Tree of Life then represents the phylogeny of organisms, i. e., the history of organismal lineages as they change through time. It implies that different species arise from previous forms via descent, and that all organisms, from the smallest microbe to the largest plants and vertebrates, are connected by the passage of genes along the branches of the phylogenetic tree that links all of Life (Figure 1).

When a person dies from cancer, the culprit is usually not the original tumor but rather the cancerous cells that spread throughout the body and replicate in distant organs, a process called metastasis. Researchers have long known that metastasizing cancer cells slip their bonds and avoid immune detection by altering the sugars on their surfaces. They've even come up with a would-be drug to prevent such sugar alterations. But that compound interferes with needed sugars on normal cells, too, with lethal results in animals. Now, Dutch researchers report that they've packaged the drug in nanoparticles targeted exclusively to cancer cells, and they've shown that this combination prevents cancer cells from metastasizing in mice.  

This video excerpt from NOVA uncovers the genetic mystery that nearly killed Alexis, now 14, and introduces the debate surrounding genetic testing at birth. After diagnosing Alexis and her twin brother Noah with cerebral palsy at a young age, doctors later discovered that the twins shared a rare genetic mutation that led to a condition that mimics cerebral palsy. The twins improved after receiving treatment, but then Alexis took a turn for the worse. Thanks to whole genome sequencing, doctors discovered a second problem linked to the mutation and gave her a different treatment that saved her life.

The Miller-Urey experiment was the first attempt to scientifically explore ideas about the origin of life. Stanley Miller simulated conditions thought be common on the ancient Earth. The purpose was to test the idea that the complex molecules of life (in this case, amino acids) could have arisen on our young planet through simple, natural chemical reactions. The experiment was a success in that amino acids, the building blocks of life, were produced during the simulation. The finding was so significant that it kick started an entirely new field of study: Prebiotic Chemistry. Scientists now have reason to believe that the gases used in the Miller-Urey simulation were not actually the same as those of the ancient atmosphere. Because of this, many experiments have since been done, testing a wide variety of atmospheres and different environmental conditions. The results are overwhelming: the molecules of life can form under a wide variety of ancient Earth-like conditions. Many questions about the origin of life remain to be answered but these findings give strong support to the idea that the first living cells on Earth may have emerged from natural chemical reactions.

Séguin, a research scientist in forest genomics with the Canadian Forest Service, inserted bacterial DNA into spruces that effectively made them immune to spruce budworm, a pest that can chew needles off tens of millions of hectares of trees in a single outbreak. While there is controversy over genetic engineering, some scientists say it could also help fight climate change by creating trees that grow bigger, faster, resist disease and can even turn carbon into a stable white powder that falls to the ground - in other words, trees that would be better at pulling carbon from the atmosphere.

In the broadest review on this topic that has been carried out to date, we found that, so far, 386 marine fish species are known to have ingested plastic debris, including 210 species that are commercially important. But findings of fish consuming plastic are on the rise. We speculate that this could be happening both because detection methods for microplastics are improving and because ocean plastic pollution continues to increase.

So you have a research assignment. Do you know where to begin? There is so much information out there on the web that it can be hard to know where to start and what path to take through the 'jungle of information'. The Research Safari is designed to help you do just that. Follow the information / inquiry process described here to help you work through your research task. There are also lots of great resources, tools and information that will help give your assignment that WOW factor. The Research Safari will help you to answer the following questions: What am I actually being asked to do for my assignment? What do I already know about the topic? Where am I going to get the information I need? How do I know that the information is accurate or 'authentic' (not fake)? Which are the best websites to use? ​What is the best way for me to present my assignment? How can I make this the best assignment ever?

Scientists have confirmed that the pathogen that causes Lyme Disease -- unlike any other known organism -- can exist without iron, a metal that all other life needs to make proteins and enzymes. Instead of iron, the bacteria substitute manganese to make an essential enzyme, thus eluding immune system defenses that protect the body by starving pathogens of iron.

Students begin by watching the online video clip and completing a worksheet. After that assignment, instructors can decide which of the two activities (or both!) to use in class. In Activity 1, students identify the locations on chromosomes of genes involved in cancer, using a set of 139 "Cancer Gene Cards" and associated posters. In Activity 2, students explore the genetic basis of cancer by examining cards that list genetic mutations found in the DNA of actual cancer patients. Small-group work spurs discussion about the genes that are mutated in different types of cancers and the cellular processes that the affected genes control. The Activity 1 and 2 Overview document provides short summaries of the two activities along with key concepts and learning objectives, background information, references and rubrics, and answers to students' questions. Both cancer discovery activities are appropriate for first-year high school biology (honors or regular), AP and IB Biology. Activity 2 is also appropriate for an undergraduate freshman biology class.

For Collinge, this led to a worrying conclusion: that the plaques might have been transmitted, alongside the prions, in the injections of growth hormone-the first evidence that Alzheimer's could be transmitted from one person to another. If true, that could have far-reaching implications: the possibility that 'seeds' of the amyloid-β protein involved in Alzheimer's could be transferred during other procedures in which fluid or tissues from one person are introduced into another, such as blood transfusions, organ transplants and other common medical procedures.

Researchers have long known that women whose families include fraternal twins are more likely to give birth to twins themselves, and they're finally starting to figure out why. After scanning data from nearly 2000 mothers of fraternal twins, scientists from eight countries found two genes that increase a woman's chance of having twins-one that affects hormone levels and another that may alter how ovaries respond to them. The second of these may also have implications for why some women respond better than others to in vitro fertilization.

Signaling at the neuromuscular junction (NMJ) is a complex process that is required for many actions that sustain life within humans. Toxins that act upon the NMJ, both natural and synthetic, act in a variety of ways to inhibit this function. This case study examines how a variety of toxins can act to disrupt the normal mechanism of function of the NMJ  by placing a protagonist ("Unlucky Chucky") at an eco-spa in Colombia with his good friend Melody. Unfortunately, during their time at the eco-spa, things don't always turn out well for Chucky. A variety of neuromuscular toxins are discussed including curare (d-tubocurarine), Botox (botulinum toxin A), physostigmine and sarin gas (GB). This case was designed to be used in a variety of classrooms ranging from an undergraduate introduction to biology course in a module focused on neuromuscular functioning, to an introduction to physiology course as an introduction to the NMJ; it could also potentially be used in a nursing course that is examining NMJ physiology.

The news that researchers want to create human-animal chimeras has generated controversy recently, and may conjure up ideas about Frankenstein-ish experiments. But chimeras aren't always man-made-and there are a number of examples of human chimeras that already exist. A chimera is essentially a single organism that's made up of cells from two or more "individuals"-that is, it contains two sets of DNA, with the code to make two separate organisms.