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POPSThe DNA Mystery: Scientists Stumped By "Telepathic" Abilities Even so, research published in ACS’ Journal of Physical Chemistry B, shows very clearly that homology recognition between sequences of several hundred nucleotides occurs without physical contact or presence of proteins. Double helixes of DNA can recognize matching molecules from a distance and then gather together, all seemingly without help from any other molecules or chemical signals. This recognition effect may help increase the accuracy and efficiency of the homologous recombination of genes, which is a process responsible for DNA repair, evolution, and genetic diversity. The new findings may also shed light on ways to avoid recombination errors, which are factors in cancer, aging, and other health issues.
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POPS"The DNA Code" - Life Hardwired in the Universe The study indicates that you don't need a miracle to arrive at the chemical cocktail for early life, just a decently large asteroid with the right components. That's all. The entire universe could be stuffed with life, from the earliest prebiotic protein-a-likes to fully DNAed descendants. The path from one to the other is long, but we've had thirteen and a half billion years so far and it's happened at least once.
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POPSChemists edge closer to recreating early life Joyce's experiment was designed to test the 'RNA World' theory, which proposes that DNA-based life evolved from a stage whereby RNA acted as both an information-storage molecule, like DNA, and as a catalyst, like enzymes, and was also capable of self-replication. This work is the biggest injection of support for the RNA world hypothesis in a long time,' says Donna Blackmond, Chair in Catalysis at Imperial College London, UK. 'It's a demonstration of principle that indefinite replication, coupled with selection via mutation, is quite plausible for RNA. The fact that it goes on indefinitely is a big thing for showing that this really could have been how life started,' she adds.
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POPSEarth's Original Ancestor Was 'LUCA' The research team compared genetic information from modern organisms to characterize the ancient ancestor of all life on earth. "Our research is much like studying the etymology of modern languages so as to reveal fundamental things about their evolution," says professor Lartillot. "We identified common genetic traits between animals, plant, bacteria, and used them to create a tree of life with branches representing separate species. These all stemmed from the same trunk – LUCA, the genetic makeup that we then further characterized." The group's findings are an important step towards reconciling conflicting ideas about LUCA. In particular, they are much more compatible with the theory of an early RNA world, where early life on Earth was composed of ribonucleic acid (RNA), rather than deoxyribonucleic acid (DNA).
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POPS'Junk' DNA proves functional Over evolutionary time, these repeats were dispersed within different species, creating new regulatory sites throughout these genomes. Thus, the set of genes controlled by these transcription factors is likely to significantly differ from species to species and may be a major driver for evolution. This research also shows that these repeats are anything but "junk DNA," since they provide a great source of evolutionary variability and might hold the key to some of the important physical differences that distinguish humans from all other species. The GIS study also highlighted the functional importance of portions of the genome that are rich in repetitive sequences.
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POPSFirst complete cancer genome sequenced Understanding the genetic basis of cancer could lead to highly personalized treatments, says Mardis. “Right now, they’re all treated the same way they were 25 years ago,” she says of AML patients. It would be nice, Mardis says, if doctors could tell their patients, “Here’s what we know about your disease, and here are your best treatment options.”
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POPSPersonal Genome Project releasing genetic data
Apparently the information being released to the PGP 10 today consists of around 20% of each volunteer's exome, a total of less than 1% of a complete genome sequence - but with the promise of much more to come. Ultimately, the PGP aims to provide complete genome sequences for all of its volunteers, which will become more and more feasible as the cost of DNA sequencing continues to plummet. There won't be any major medical breakthroughs from analysis of the PGP10 data, but this is a tremendous first step in the direction of personalised medicine. It's also an important experiment to see whether the noble open-access model of the PGP can survive contact with reality. As Church notes in the NY Times article: "We don't yet know the consequences of having one's genome out in the open. But it's worth exploring." Anyone who's interested in getting their genome sequenced by the PGP - and sharing the resulting information with the world - should consider registering for inclusion.
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POPSStudy finds value in 'junk' DNA "Alu elements are a major source of new exons. Because Alu is a primate-specific retrotransposon, creation of new exons from Alu may contribute to unique traits of primates, so we want to better understand this process," said the study's senior author Yi Xing, Ph.D., assistant professor of internal medicine and biomedical engineering, who holds a joint appointment in the University of Iowa Carver College of Medicine and the UI College of Engineering. To study the impact of Alu-derived exons on human gene expression, the researchers used a high-density exon microarray. The technology has nearly six million probes for monitoring the expression patterns of all human exons. Using data generated by these microarrays, the scientists analyzed 330 Alu-derived exons in 11 human tissues. The team then identified a number of exons with interesting expression and functional characteristics.
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POPSComputing with RNA That opens up the possibility of computing devices that can respond to specific conditions within the cell, he says. For example, it may be possible to develop drug delivery systems that target cancer cells from within by sensing genes used to regulate cell growth and death. "You can program it to release the drug when the conditions are just right, at the right time and in the right place," these biocomputers are built from three main components--sensors, actuators, and transmitters--all of which are made up of RNA. The input sensors are made from aptamers, RNA molecules that behave a bit like antibodies, binding tightly to specific targets. Similarly, the output components, or actuators, are made of ribozymes, complex RNA molecules that have catalytic properties similar to those of enzymes. These two components are joined by yet another RNA molecule that serves as a transmitter, which is activated when a sensor molecule recognizes input chemical and triggers an actuator molecule
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POPSTuberculosis Is 9,000 Years Old The fact that Alit-Yam is one of the first Neolithic settlements evidenced to have domesticated cattle further goes to show that the bacteria infected humans first and then mutated into its bovine form. Several more skeletons found at the dig site exhibited traces of bacterial cell wall lipids, which have been directly linked to the presence of TB after DNA analysis. Having discovered the first hosts of the TB bacteria, biologists now hope to be able to sequence the bacterial DNA, in the hope that they would find out exactly how it mutated over the thousands of years it lived in humans. Already, several strand portions have been identified in samples collected from the bones in Egypt, which are not present in today's TB strains. This could mean that changes in human physiology may also trigger alternate responses in bacterial morphology. Scientists continue their research, with the big prize being finding a way of ridding humanity of this terrible disease.
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POPSScientists Create World's Thinnest Balloon Other potential applications include hyper-fine sensors and ultra-pure filters. "Once you have a membrane that won't let anything past, the most interesting thing is to then poke a hole in it. Then you can detect what leaks through that hole with high sensitivity, or make sure only what you want leaks through that hole," McEuen said. The only way gas leaked out from inside the balloons was through the glass that the bubbles were anchored on, McEuen explained.
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POPSWere Ancient Viruses a Key to Human Evolution? These viral fragments are fossils that reside within each of us, carrying a record that goes back millions of years. Because they no longer seem to serve a purpose or cause harm, these remnants have often been referred to as “junk DNA.” Although many of these evolutionary relics still manage to generate proteins, scientists have never found one that functions properly in humans or that could make us sick. That is until Thierry Heidmann who runs the laboratory at the Institut Gustave Roussy, on the southern edge of Paris, brought one to life. Heidmann long suspected that if a retrovirus happens to infect a human sperm cell or egg, which is rare, and if that embryo survives—which is rarer still—the retrovirus could have the evolutionary power to influence humans as a species becoming part of the genetic blueprint, passed from mother to child, and from one generation to the next, much like a gene for eye color or asthma.
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POPSWhat Do Your Genes Say About You? The Future of Personal Genomics The company 23andMe announced its DNA testing service last month in San Diego. You might think such a comprehensive analysis would costs thousands, but the process is actually relatively affordable. For less than $1,000 customers are able to learn virtually everything science currently knows about their biological code. For those wary of needles, you’ll be comforted to know that the DNA is retrieved conveniently and painlessly from a home mail-in saliva test kit.
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POPS1998: Syphilis Genome Sequenced; 2008: Syphilis on the Rise Incidence is up among women, African-Americans and, most prominently, gay men, who account for 64 percent of the more than 12,000 people diagnosed last year with either primary or secondary syphilis infections. Primary infections appear as ulcers or shankers on the genitals, anus or mouth; secondary infections result in rashes on the foot's sole or the palm of the hand as well as hair loss and lesions on or around the genitalia.
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POPSWill "Th!nk" Ignite an Electronic Car Revolution in the U.S.? Think City is one of two models that are out already, together with the Think Ox, with a choice of either lithium or a sodium battery, it's range is enough to take a suburban dweller to the downtown office and back, with zero carbon footprint. The car is thoughfully fully computerized and allows a key-less entry. It features real time navigation, web, e-mail and open source interfaces, intelligent and sustainable driving and route calculations. The DNA-key gives the user feedback on charging status and sends messages, for example, for pre-heat or pre-cool options via GPRS. Pricing has yet to be announced, but the company's current vehicles cost less than $25,000.
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POPSElectrostatic-based DNA Microarray Technique Could Revolutionize Medical Diagnostics "One of the most amazing things about our electrostatic detection method is that it requires nothing more than the naked eye to read out results that currently require chemical labeling and confocal laser scanners," said Jay Groves, a chemist with joint appointments at Berkeley Lab's Physical Biosciences Division and the Chemistry Department of the University of California (UC) at Berkeley, who led this research. "We believe this technique could revolutionize the use of DNA microarrays for both research and diagnostics."
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POPSFive Reasons Why Aliens Will Make Contact with the Japanese First North Korea is rumored to have recently released a statement claiming that their nuclear reactor has the dual capability of communicating wirelessly with alien species up to 1,000 light years away in real time. Of course, we can't believe everything that the North Korean government says, but seriously, I wouldn't be surprised at all if they were already communicating with other planets. If that's the case, it should be relatively easy for Japan, a neighboring country, to intercept their signals with laser pulses and let the world know definitively what Kim Jong Il has known for decades—that there is life beyond Earth.
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POPSHuge hidden biomass lives deep beneath the oceans They found simple organisms known as prokaryotes in every sample. Prokaryotes are organisms that often have just one cell. Their peculiarity is that, unlike any other form of life, their DNA is not neatly packed into a nucleus.
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POPSHumanity Was Genetically Divided For 100,000 Years the study provides insight into the early demographic history of human populations before they moved out of Africa. “These early human populations were small and isolated from each other for many tens of thousands of years,” says Rosset. MtDNA, inherited down the maternal line, was used in 1987 to discover the age of the famous “Mitochondrial Eve,” the most recent common female ancestor of everyone alive today. This work has since been extended to show unequivocally that “Mitochondrial Eve” was an African woman who lived sometime during the past 200,000 years.
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POPSEvolution: 24 myths and misconceptions So here is New Scientist's guide to some of the most common myths and misconceptions about evolution.Everything is an adaptation produced by natural selection Natural selection is the only means of evolution Natural selection leads to ever-greater complexity Evolution produces creatures perfectly adapted to their environment Evolution always promotes the survival of species It doesn't matter if people do not understand evolution "Survival of the fittest" justifies "everyone for themselves" Evolution is limitlessly creative Evolution cannot explain traits such as homosexuality Creationism provides a coherent alternative to evolution
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POPSDNA Testing Confirms Mankind's African Origins Also, they noted, they found a close a relationship between the Yakut population of Siberia and native Americans, who are believed to have migrated from Siberia via a land bridge at a time of lower sea levels. The research was supported by the National Institutes of Health.
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POPSIBM Is Working on DNA-Based processors This new goal is an addition to the research on the "DNA origami," conducted by Paul Rothemund of California Institute of Technology. Currently, more and more researchers are turning to DNA in search of an older goal, the "self-assembly". The advantages of building semiconductors based on DNA and nanotubes are especially concerning the chips' size, given the fact that DNA can work at a 2-nanometer scale. Imagine a chip built at two-nanometer node, then compare it to a state-of-the-art processor built with the 45-nanometer production node.
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