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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.

The researchers isolated different subpopulations of human brain stem cells and precisely identified, which genes are active in which cell type. In doing so, they noticed the gene ARHGAP11B: it is only found in humans and in our closest relatives, the Neanderthals and Denisova-Humans, but not in chimpanzees. This gene manages to trigger brain stem cells to form a bigger pool of stem cells. In that way, during brain development more neurons can arise and the cerebrum can expand. The cerebrum is responsible for cognitive functions like speaking and thinking.

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 watermen find wounded fish along a lonely river in Maryland, they kick off a scientific debate and an environmental crisis focused on a mysterious microbe that may -- or may not -- cause sick fish and sick people. Watch the title sequence from this award-winning, hour-long film.

Sub-Saharan Africa is the most genetically diverse region in the world." The rates of susceptibility and not only whether or not someone becomes ill, but also whether or not they live or die, or even display symptoms, varies widely. The genetics of both this deadly strain of Ebola itself, and of the populations living in the affected areas, are at the forefront of the efforts by Dr. Moses as she works with Dr.Pardis Sabeti at Harvard to provide samples for genome sequencing.

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

This video segment adapted from NOVA scienceNOW examines the realm of personal DNA testing. It describes the latest tests, which look for single-nucleotide polymorphisms (SNPs). These single-letter differences in DNA sequence make humans unique from one another but may also predispose people to certain diseases. The video also discusses the Personal Genome Project, an extension of the Human Genome Project aimed at determining the root causes of many common diseases. The Personal Genome Project takes into account personal genomics as well as lifestyle information, such as one's living environment, habits, and behaviors.

3:16 video

On June 14, 2013, the Smithsonian Institution in Washington, D.C. opened the high-tech, high-intensity exhibition Genome: Unlocking Life's Code to celebrate the 10th anniversary of researchers producing the first complete human genome sequence - the genetic blueprint of the human body - in April 2003. The exhibition is a collaboration between the Smithsonian's National Museum of Natural History (NMNH) and the National Human Genome Research Institute (NHGRI) of the National Institutes of Health.

Over the last decade, as DNA-sequencing technology has grown ever faster and cheaper, our understanding of the human genome has increased accordingly. Yet scientists have until recently remained largely ham-fisted when they've tried to directly modify genes in a living cell. Take sickle-cell anemia, for example. A debilitating and often deadly disease, it is caused by a mutation in just one of a patient's three billion DNA base pairs. Even though this genetic error is simple and well studied, researchers are helpless to correct it and halt its devastating effects.

The following sequence of activities is designed to help your students continue their investigation into how characteristics of living things are passed on from generation to generation. This time we are looking at multifactorial traits and how the genes and environment play a role in the final expression of the trait.

The study by researchers from the Wellcome Trust Sanger Institute and collaborators at La Trobe University in Melbourne and several other Australian institutes, challenges a previous theory that suggested an influx of people from India into Australia around 4-5 thousand years ago. This new DNA sequencing study focused on the Y chromosome, which is transmitted only from father to son, and found no support for such a prehistoric migration. The results instead show a long and independent genetic history in Australia.

This two-hour special, hosted by ABC "Nightline" correspondent Robert Krulwich, chronicles the fiercely competitive race to capture one of the biggest scientific prizes ever: the complete letter-by-letter sequence of genetic information that defines human life-the human genome. NOVA tells the story of the genome triumph and its profound implications for medicine and human health.

The goal of RI-ITEST is to prepare diverse students for careers in information technologies by engaging them in exciting, inquiry- based learning activities that use sophisticated computational models in support of a revolutionary science curriculum. Teachers will incorporate interactive computer models developed under the Science of Atoms and Molecules (SAM) project at the Concord Consortium. These materials were specifically designed to support a deeper understanding of science made possible through interactive computer simulations and the new physics-chemistry-biology sequence. Connections will be made between the models students use to learn science and possible careers in research and industry where computer modeling is used.

As the genomes of more and more species are sequenced, geneticists are piecing together an extraordinarily detailed picture of the molecules that are fundamental to life on Earth. With modern techniques, we can not only trace how the bodies of animals have evolved, we can even identify the genetic mutations behind these changes and, as we recently reported, genes sometimes evolve in surprising ways. Here though, in celebration of the versatility of DNA, New Scientist presents five classic examples of gene evolution.

Men shed more bacteria into their surroundings than women do, studies have shown. Now scientists have found that men and women have different effects on the variety of bacteria inside a home, too. The variation comes down to skin biology and "perhaps to body size and hygiene practices," note researchers who sequenced the genes in dust that had settled on the tops of doors in 1,200 homes across the U.S. Dogs apparently alter indoor bacteria more extensively than humans or cats. The bacterial signatures of each of these living beings are unique enough that by simply testing dust in a home, investigators can accurately predict if more women or men live there and if dogs or cats do as well.

A dynamic 3D computer animated video takes you "inside" for a close-up look at how we're made. Watch as the mysteries of the Human Genome are literally "unraveled." 3D modeling and animation created by Bill Baker, Bakedmedia, Inc. and Mike Fisher for the National Human Genome Research Institute.

Why does a snake have 25 or more rows of ribs, whereas a mouse has only 13? The answer, according to a new study, may lie in "junk DNA," large chunks of an animal's genome that were once thought to be useless. The findings could help explain how dramatic changes in body shape have occurred over evolutionary history. Scientists began discovering junk DNA sequences in the 1960s. These stretches of the genome-also known as noncoding DNA-contain the same genetic alphabet found in genes, but they don't code for the proteins that make us who we are. As a result, many researchers long believed this mysterious genetic material was simply DNA debris accumulated over the course of evolution. But over the past couple decades, geneticists have discovered that this so-called junk is anything but. It has important functions, such as switching genes on and off and setting the timing for changes in gene activity. 

DNA has a double helix structure. If untwisted, DNA looks like two parallel strands. Each strand has a linear sequence of A, C, G, and T. The precise order of the letters carries the coded instructions. One strand is a complementary image of the other: A always pairs with T, and C always pairs with G.

Interactive requiring shockwave:  Replicate DNA, transcribe and translate a sequence of virtual DNA.  Reading and information includied.  Good webquest component.