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An international team led by Professor Itai YanaAi of the Technion-Israel Institute of Technology Department of Biology made the discovery after using an extraordinarily powerful technique known as CEL-Seq. CEL-Seq monitors individual cells for their gene activity (as detected via mRNA)-and they applied it across 10 different species, with CEL-Seq being applied to 70 embryos per species. In particular, they were interested in whether the animal classification of phylum-which separates animals into groups according to their body plans-is actually a useful tool for placing animals into groups, as well as what genetic attributes are the same and different between the different phyla.

Despite existing for hundreds of years, the science of classification is far from dead. Classification of many species, old and new, continues to be hotly disputed as scientists find new information or interpret facts in new ways. Arguments are fierce and species do change names, but only after a wealth of information has been gathered to support such a big step. One of the new reasons why species are being re-evaluated is because of DNA analysis.

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 use DNA profiling to determine who robbed a bank. After they learn how the FBI's Combined DNA Index System (CODIS) is used to match crime scene DNA with tissue sample DNA, students use CODIS principles and sample DNA fragments to determine which of three suspects matches evidence obtain at a crime location. They communicate their results as if they were biomedical engineers reporting to a police crime scene investigation.

Taylor must write a report about a natural toxin while she is home from college on break. After a family dinner conversation about the latest attempt to poison a politician via a letter, Taylor decides to explore how ricin acts as a poison. Students work in small groups to help Taylor by working through figures from primary literature papers and exploring the use of an in vitro translation system, sucrose gradient fractionation and the effect of inhibiting various steps of translation.  A shorter, second day activity involves students looking further at the effect of ricin upon ribosome function and at the ricin protein itself.  Students individually complete a cumulative assignment of writing a letter back to Mom and Dad about how ricin has its effects. This case was designed for use in a second semester biochemistry course or a molecular biology course that incorporates the mechanism of transcription. Prerequisite knowledge includes a general understanding of the steps of translation and the ability to interpret data from agarose gels.

Because the gene-enzyme system forms a closed loop, it presents us with a classic chicken or egg conundrum: Which came first, genes or the protein enzymes they code for? While the details are still not fully worked out, discoveries over the past few decades have lead researchers to a surprising possible solution: What really came first? Genes that act as enzymes! The RNA World Hypothesis is the idea that before living cells, the genetic code, and the gene/protein cycle ever existed, chains of a chemical called RNA were forming naturally. Once formed, some of these chains were able to function as enzymes, and were even able to evolve by making copies of themselves with slight, accidental modifications.

Ever wonder how your brain processes information? These brain tricks and illusions help to demonstrate the two main systems of Fast and Slow Thinking in your brain.

This case study examines the molecular methods that were used to reverse engineer the 1918 influenza virus strain in order to try and solve the mystery of why it was so deadly. The story starts in the 1950s with the unsuccessful attempts to culture the influenza virus and follows scientists through to the turn of the century when cutting edge molecular tools enabled scientists to finally resurrect the 1918 virus through reverse genetics. The history and methods involved in resurrecting this deadly virus are reviewed in class with a PowerPoint presentation containing clicker questions (answered with a personal response system) and discussion questions (answered in small groups). This "clicker case" is suitable for high school biology and lower division undergraduate biology classes for non-majors. It could also be used in any lower division non-major class focused on human disease and the history of human disease.

In a unique twist on human genomics studies that seek to identify genetic variants linked to human disease, researchers have combined whole-exome sequencing of 50,726 adults with the individuals' long-term electronic health record (EHR) data. The effort, by researchers at the Geisinger Health System in Pennsylvania and Regeneron Genetics Center, a subsidiary of New York-based Regeneron Pharmaceuticals, has yielded novel disease-linked variants, including loss-of-function alleles. The team behind the project, called DiscovEHR, has also found that about one in 30 of the individuals harbors a deleterious genetic variant for which a screen or treatment already exists. The group's analysis is described in two papers published today (December 22) in Science.

The Ebola epidemic that tore through West Africa in 2014 claimed 11,310 lives, far more than any previous outbreak. A combination of factors contributed to its savagery, among them a mobile population, crumbling public health systems, official neglect and hazardous burial practices. But new research suggests another impetus: The virus may have evolved a new weapon against its human hosts. In studies published on Thursday in the journal Cell, two teams of scientists report that a genetic mutation may have made Ebola more deadly by improving the virus's ability to enter human cells.

DNA acquired from breeding with Neanderthals may explain why people of European descent respond differently to infection than those of African descent, two studies suggest. The findings might also offer insight into why people of African descent are more prone to autoimmune diseases caused by an overactive immune system.

From something as small and complex as a chromosome to something as seemingly simple as the weather, sex determination systems vary significantly across the animal kingdom. Biologist and teacher Aaron Reedy shows us the amazing differences between species when it comes to determination of gender.

When you eat something loaded with sugar, your taste buds, your gut and your brain all take notice. This activation of your reward system is not unlike how bodies process addictive substances such as alcohol or nicotine -- an overload of sugar spikes dopamine levels and leaves you craving more. Nicole Avena explains why sweets and treats should be enjoyed in moderation.

This case study focuses on the relationship between evolution and plasticity using a hands-on, inquiry-based approach. Students view examples from the literature that illustrate the difference between nature and nurture, or the relative contributions of genes and the environment in shaping phenotypes. Using the Trinidadian guppy system as an example, students learn about seminal work in the field in addition to exploring quantitative genetic techniques used to partition phenotypic variance between genes (G) and the environment (E). They use real data from one of the publications cited in the case to graph reaction norms illustrating GxE interactions at the family and population level. The inquiry-based approach means that students are introduced to new concepts in a stepwise fashion, and asked to develop and build their understanding using causal, explanatory evidence. The case concludes with an exercise in which students apply their knowledge to a real conservation problem in Trinidad and Tobago, where guppies are native. This case would be appropriate for an upper level biology, genetics, or evolution course.

In the August 1 issue of CELL, researchers from the Gene and Stem Cell Therapy Program at Sydney's Centenary Institute revealed another function of introns, or noncoding nucleotide sequences, in DNA. They reported that gene-sequencing techniques and computer analysis allowed them to demonstrate how granulocytes use noncoding DNA to regulate the activity of a group of genes that determines the cells' shape and function.

Loss of species richness is often due to anthropogenic activity. The global decline of amphibians is one such example. This case study examines the impact of road deicing agents on amphibians living near bridges and roads treated heavily with salt during the winter months. Concepts explored in this case include changes to the aquatic environment as a result of road deicing applications, bioaccumulation, osmoregulation in amphibians living in clean freshwater, and the impact of increased aquatic salinity levels on the ability of amphibians to adequately osmoregulate in an environment for which they are not adapted. Three short videos created by the author can be shown in class or assigned for viewing in advance for a "flipped" classroom approach. Originally developed for a general education/introductory biology course, the case could also be used with introductory level animal anatomy and physiology courses as part of a deeper exploration of the renal system.

This case study was inspired by the Zika virus outbreak that occurred around the time of the 2016 Olympic Games. Many athletes were fearful of attending because of the link between Zika virus infection and microcephaly in infants. This concern, however, ran contrary to reports suggesting that the risk of athletes and other travelers becoming infected was remarkably low. Jessica, a fictional Olympic equestrian and the main character of the case, was unfortunately very unlucky and contracted Zika virus near the time of the Games. She ended up enduring negative health complications likely as a consequence of the infection.  This case was designed to be implemented in the nervous system unit of a human biology or anatomy and physiology course. The case is also appropriate for microbiology and public health courses.   Students are expected to have foundational knowledge in viral life cycles, and will explore disruptions in neurotransmission as well as abnormal fetal brain development.

At the annual meeting of the American Association for Cancer Research in Washington DC this week, Wolchok and other researchers will report on their search for immunotherapy markers - ways to predict a patient's response to an immunotherapy or to show whether a given treatment is working. The work is hampered by the complexity of the immune system, but early results are converging on one point: that patients' own immune responses to cancer are crucial in determining outcomes.

The American Joint Committee on Cancer (AJCC) and the International Union for Cancer Control (UICC) maintain the TNM classification system as a tool for doctors to stage different types of cancer based on certain standards. It's reviewed every 6 to 8 years to include advances in our understanding of cancer.

In the 2013 Holiday Lectures on Science, Charles L. Sawyers of Memorial Sloan-Kettering Cancer Center and Christopher A. Walsh of Boston Children's Hospital will reveal the breathtaking pace of discoveries into the genetic causes of various types of cancers and diseases of the nervous system, and discuss the impact of those discoveries on our understanding of normal human development and disease.