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Archive - Oct 6, 2015

Giraffe Neck Evolution Traced to Two Key Stages of Lengthening in a Single Vertebra (C3); the Two Lengthenings Took Place 6 Million Years Apart and in Different Directions

Scientists have long theorized that the long neck of modern-day giraffes evolved to enable them to find more vegetation or to develop a specialized method of fighting. A new study of fossil cervical vertebrae reveals the evolution likely occurred in several stages as one of the animal's neck vertebrae stretched first toward the head and then toward the tail a few million years later. The study's authors say the research shows, for the first time, the specifics of the evolutionary transformation in extinct species within the giraffe family. "It's interesting to note that that the lengthening was not consistent," said Dr. Nikos Solounias, a giraffe anatomy expert and paleontologist at the New York Institute of Technology (NYIT) College of Osteopathic Medicine. "First, only the front portion of the C3 vertebra lengthened in one group of species. The second stage was the elongation of the back portion of the C3 neck vertebra. The modern giraffe is the only species that underwent both stages, which is why it has a remarkably long neck."The study, which includes a computational tracking model of the evolutionary elongation, was published online on October 7, 2015 in an open-access article in the journal Royal Society Open Science. The article is titled "Fossil Evidence and Stages of Elongation of the Giraffa camelopardalis Neck." Dr. Solounias and Melinda Danowitz, a medical student in the school's Academic Medicine Scholars program, studied 71 fossils of nine extinct and two living species in the giraffe family. The bones, discovered in the late 1800s and early 1900s, were housed at museums around the world, including ones in England, Austria, Germany, Sweden, Kenya, and Greece. "We also found that the most primitive giraffe already started off with a slightly elongated neck," said Danowitz.

Downregulation of KLK4 Gene Detected in East Asians; May Contribute to Specific Dental Traits and Eczema Resistance Found in Asians

Dr. Susana Seixas of the Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP), Porto, Portugal, and colleagues have found key differences in a suite of genes important for skin and bone development that may have bestowed specific advantages amongst Asians. The new research was published online on September 29, 2015 in Molecular Biology and Evolution. The article is titled “Adaptive Evolution Favoring KLK4 Downregulation in East-Asians.” The researchers focused on the human kallikrein cluster (KLK), a suite of fifteen genes clustered on the long arm of chromosome 19 that play a key role in human adaptation and reproductive biology. The genes function as molecular scissors called serine proteases, which target and clip other proteins involved in semen function, teeth development, skin and blood pressure maintenance, and even cancer. The team undertook a large study to identify 1,419 DNA differences in the KLK genomic cluster amongst Eastern Asian (Han Chinese and Japanese), African, and European populations by using new DNA data from the recently completed 1000 Genomes project. The most striking differences were narrowed down to two regions near the KLK4 gene, which were found to severely hamper the activity of KLK4 only in Asian populations. This KLK4 downregulation may contribute to dental traits typically found in Asians and be important in controlling skin conditions like eczema, which is much more prevalent in northern Europe than in Asia. "We further predict many effects related to male biology and other physiological functions with possible outcomes in human complex diseases, said Dr. Seixas.

Knees Evolved First in Spiders, by Duplication of “dachshund” Gene

Dr. Nikola-Michael Prpic and colleagues from Abteilung für Entwicklungsbiologie, GZMB Ernst-Caspari-Haus, Johann-Friedrich-Blumenbach-Institut für Zoologie und Anthropologie, Georg-August-Universität, Göttingen, Germany, have identified the driving force behind the evolution of a leg novelty first found in spiders: knees. They report their findings in a new study published online on October 6, 2015 in Molecular Biology and Evolution, The article is titled “Neofunctionalisation of a Duplicate dachshund Gene Underlies the Evolution of a Novel Leg Segment in Arachnids.” With eight legs and seven joints on each---that's a lot for a spider to coordinate just to take a single step. Dr. Prpic's research team homed in on a gene called dachshund (dac). This gene was first discovered in fruit flies, and humorously named for the missing leg segments and shortened legs that result from dac mutant flies. But arachnids are different from flies and other arthropods, possessing a second dac gene. And the second dac gene (dac2) is expressed only in the kneecap, or patella, during spider development. When the research group used RNA interference experiments to specifically deactivate dac2, the kneecap fuses with the tibia to form a single leg segment. The force behind knees first appearing on the spider evolutionary scene was a result of ancient gene duplication in the original dac gene that, over time, evolved into an entirely new function and way of unique way of walking about for spiders. "Species constantly adapt and evolve by inventing new body features," said Dr. Prpic. "Our work shows how a gene can be duplicated and then used during evolution to invent a new morphological feature."

Emmanuelle Charpentier and Jennifer Doudna Share $500,000 Gruber Genetics Prize for Landmark Discovery of RNA-Guided CRISPR/Cas9 Editing System; Prize to Be Awarded Friday, October 9, at ASHG Annual Meeting

The 2015 Gruber Genetics Prize will be awarded this year to microbiologist Emmanuelle Charpentier, Ph.D., of the Helmholtz Centre for Infection Research in Braunschweig, Germany, and biochemist Jennifer Doudna, Ph.D., of the University of California, Berkeley. These two eminent scientists are being recognized for their joint creation of a revolutionary gene-editing technology known as CRISPR/Cas9, which functions as a molecular scissor, generating double-stranded cuts in targeted DNA molecules with exceptional precision. The technology is being used around the world to advance biological research and to engineer genes for developing powerful new therapies for a wide range of human diseases, as well as new biofuels and agricultural products. The award will be presented to Dr. Charpentier and Dr. Doudna in Baltimore, Maryland, on Friday, October 9, during the 2015 annual meeting of the American Society of Human Genetics (ASHG). “The discovery of the CRISPR/Cas9 cellular defense system has transformed molecular genetics,” said Utpal Banerjee, Ph.D., a member of the Selection Advisory Board to the Prize. Dr. Banerjee is Professor and Chair of the Department of Molecular, Cell, and Developmental Biology at UCLA. He did his post-doctoral fellowship in the laboratory of the renowned Seymour Benzer, Ph.D. “We now have a quick and highly accurate technology for deleting or adding specific pieces of DNA, an advance with wide-ranging implications for both basic science and clinical medicine,” Dr. Banerjee added. Dr. Charpentier and Dr. Doudna began their collaboration in 2011 after meeting at a scientific conference in Puerto Rico. Both had been trying to unlock the molecular mysteries of the CRISPR systems, an unusual repeating sequence of DNA that enables bacteria to mount a successful defense against viral invaders.

Two Young Women Geneticists Receive 2016 Rosalind Franklin Young Investigator Award; Mary-Claire King Comments

The Genetics Society of America (GSA), the American Society for Human Genetics (ASHG), and The Gruber Foundatio recently announced that Maria Barna, Ph.D., of Stanford University; and Carolyn McBride (photo), Ph.D., of Princeton University, are the 2016 recipients of the Rosalind Franklin Young Investigator Award. The Rosalind Franklin Young Investigator Award is funded by The Gruber Foundation and is awarded every three years to two women geneticists at the beginning of their independent research careers. Winners are selected by a joint committee appointed by the GSA and the ASHG from nominees from around the world. The award recognizes outstanding genetics research in two categories: mammalian genetics, including human genetics; and non-mammalian genetics. Each winner will receive a $75,000 award to be used as she chooses for her research. “The Rosalind Franklin Award celebrates the accomplishments of the next generation of young women scientists, who are following the path laid down by our fore-mothers,” said Mary-Claire King, Ph.D., Chair of the Rosalind Franklin Award committee and Professor of Genome Sciences and Medicine (Medical Genetics) at the University of Washington. Dr. King is world-famous for her seminal research into the genetics of breast cancer, which largely enabled the identification of both the BRCA1 and BRCA2 breast cancer genes. “Reading the creative work of these remarkable young women is a great joy for the committee. We congratulate the winners and send our very best wishes for continued success to all the nominees.” Dr. Barna, the 2016 recipient in human and mammalian genetics, uses mouse genetics to understand how ribosomes process information to create proteins for different types of cells and tissues. Dr. Barna received her bachelor’s degree in anthropology from New York University and her Ph.D.

ASHG TV Debuts at ASHG 2015 Annual Meeting in Baltimore (Oct 6-10); Details Here on How to Watch Web TV Coverage of This Major Human Genetics Conference

WebsEdge is going to be in Baltimore as the official broadcaster at the American Society of Human Genetics (ASHG) 2015 Annual Meeting (www.ashg.org/2015meeting), for the first ASHG TV. To be held October 6-10 at the Baltimore Convention Center, the conference will welcome approximately 6,500 human genetics specialists. ASHG TV will broadcast a new daily show bringing together thought leaders and newsmakers from around the event. In addition, ASHG TV will be premiering a number of films from leading institutions in genetics from around the world. Preview which ones will be feature on ASHG TV at https://www.youtube.com/watch?list=PL9CZabk3nD4EgOiCp7t0l-tGlmC3CjVBM&v=.... During the conference, you will be able to watch ASHG TV on screens around the Baltimore Convention Center. Excitingly, you can also view ASHG TV in the following hotels on the indicated channels: Hilton 51, Sheraton 42, Renaissance 82, Hyatt Regency 50, and Marriott Inner Harbor 19. You can also watch ASHG TV at http://www.websedge.com/videos/ashg_tv/#/ and on YouTube at https://www.youtube.com/playlist?list=PL9CZabk3nD4EgOiCp7t0l-tGlmC3CjVBM. Follow WebsEdge, ASHG TV, and the meeting on Twitter at: @WebsEdge_Health| #ASHG15 | @GeneticsSociety WebsEdge/Health – our online channel for Health related organizations, including ASHG TV at http://www.websedge.com/videos/ashg_tv/#/.

Ancient Alga Developed Crucial Set of Genes to Interact with Beneficial Land Fungi Prior to Moving from Sea to Land and Then Evolving into Earth’s First Land Plant

A team of scientists led by Dr. Pierre-Marc Delaux [John Innes Centre (UK) / University of Wisconsin-Madison (USA)] has solved a long-running mystery about the first stages of plant life on earth. The team of scientists from the John Innes Centre, the University of Wisconsin-Madison, and other international collaborators, has discovered how an ancient alga was able to inhabit land, before it went on to evolve into the world's first plant and colonize the earth. The research was published online on October 5, 2015 in PNAS. The article is titled “Algal Ancestor of Land Plants Was Preadapted for Symbiosis.” Up until now, it had been assumed that the alga evolved the capability to source essential nutrients for its survival after it arrived on land by forming a close association with a beneficial fungus called arbuscular mycorrhiza (AM), which still exists today and which helps plant roots obtain nutrients and water from soil in exchange for carbon. The previous discovery of 450-million-year-old fossilized spores similar to the spores of the AM fungus suggests this fungus would have been present in the environment encountered by the first land plants. Remnants of prehistoric fungi have also been found inside the cells of the oldest plant macro-fossils, reinforcing this idea. However, scientists were not clear as to how the algal ancestor of land plants could have survived long enough to mediate a quid pro quo arrangement with a fungus. This new finding points to the alga developing this crucial capability while still living in the earth's oceans! Dr.

Fundamental Flaw Found in GC-MS Technology; “Astoundinhg Results” from Scripps Research Institute Suggest Heat from GC-MS Process Can Dramatically Change the Chemical Composition of Samples

A new study led by scientists at The Scripps Research Institute (TSRI) shows that a technology used in thousands of laboratories, called gas chromatography-mass spectrometry (GC-MS), fundamentally alters the samples it analyzes. “We found that even relatively low temperatures used in GC-MS can have a detrimental effect on small molecule analysis,” said study senior author Dr. Gary Siuzdak, Senior Director of TSRI’s Scripps Center for Metabolomics and Professor of Chemistry, Molecular and Computational Biology. Using new capabilities within XCMS, a data analysis platform developed in the Siuzdak lab, the researchers observed small molecules transforming—and even disappearing—during an experiment meant to mimic the GC-MS process, throwing into question the nature of the data being generated by GC-MS. The study was published online on October 4, 2015 in Analytical Chemistry. The article is titled ““Thermal Degradation of Small Molecules: A Global Metabolomic Investigation.” For more than 50 years, chemists and biologists have used GC-MS to identify and measure concentrations of small molecules. When a sample is injected into a GC-MS system, it is heated and vaporized. The vapor travels through a gas chromatography column and the molecules separate, allowing the mass spectrometer to measure the individual molecules in the sample. Today, GC-MS is widely used in thousands of laboratories for tasks such as chemical analysis, disease diagnosis, environmental monitoring, and even forensic investigations. The new experiments were initiated when Dr. Siuzdak was preparing a short course for students at the American Society for Mass Spectrometry annual meeting. The question arose as to how heat from the GC-MS vaporization process could affect results, so Dr. Siuzdak and TSRI Research Associate Dr.