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Reuters With the right expertise in molecular biology, one could start a basic laboratory to modify human embryos using a genome-editing computer technique all for a couple thousand dollars, according to a new report. Genetic modification has received heightened scrutiny recently following last week’s announcement that Chinese researchers had, for the first time, successfully edited human embryos’ genomes. The team at Sun Yat-Sen University in Guangzhou, China, used CRISPR (clustered regularly interspaced palindromic repeats), a technique that relies on “cellular machinery” used by bacteria in defense against viruses. This machinery is copied and altered to create specific gene-editing complexes, which include the wonder enzyme Cas9. The enzyme works its way into the DNA and can be used to alter the molecule from the inside. The combination is attached to an RNA guide that takes the gene-editing complex to its target, telling Cas9 where to operate. Use of the CRISPR technique is not necessarily relegated to the likes of cash-flush university research operations, according to a report by Business Insider.
Geneticist George Church, who runs a top CRISPR research program at the Harvard Medical School, said the technique could be employed with expert knowledge and about half of the money needed to pay for an average annual federal healthcare plan in 2014 -- not to mention access to human embryos. "You could conceivably set up a CRISPR lab for $2,000,” he said, according to Business Insider. Other top researchers have echoed this sentiment. "Any scientist with molecular biology skills and knowledge of how to work with [embryos] is going to be able to do this,” Jennifer Doudna, a biologist at the University of California, Berkeley, recently told MIT Tech Review, which reported that Doudna co-discovered how to edit genetic code using CRISPR in 2012. Last week, the Sun Yat-Sen University research team said it attempted to cure a gene defect that causes beta-thalassemia (a genetic blood disorder that could lead to severe anemia, poor growth, skeletal abnormalities and even death) by editing the germ line. For that purpose they used a gene-editing technique based on injecting non-viable embryos with a complex, which consists of a protective DNA element obtained from bacteria and a specific protein. "I suspect this week will go down as a pivotal moment in the history of medicine," wrote science journalist Carl Zimmer for National Geographic. Response to the new research has been mixed. Some experts say the gene editing could help defeat genetic diseases even before birth. Others expressed concern. “At present, the potential safety and efficacy issues arising from the use of this technology must be thoroughly investigated and understood before any attempts at human engineering are sanctioned, if ever, for clinical testing,” a group of scientists, including some who had worked to develop CRISPR, warned in Science magazine. Meanwhile, the director of the US National Institutes for Health (NIH) said the agency would not fund such editing of human embryo genes. “Research using genomic editing technologies can and are being funded by NIH,” Francis Collins said Wednesday. “However, NIH will not fund any use of gene-editing technologies in human embryos. The concept of altering the human germline in embryos for clinical purposes ... has been viewed almost universally as a line that should not be crossed.” Although the discovery of CRISPR sequences dates back to 1987 – when it was first used to cure bacteria of viruses – its successes in higher animals and humans were only achieved in 2012-13, when scientists achieved a revolution by combining the resulting treatment system with Cas9 for the first time. On April 17, the MIT’s Broad Institute announced that has been awarded the first-ever patent for working with the Crisp-Cas9 system. The institute’s director, Eric Lander, sees the combination as “an extraordinary, powerful tool. The ability to edit a genome makes it possible to discover the biological mechanisms underlying human biology.” The system’s advantage over other methods is in that it can also target several genes at the same time, working its way through tens of thousands of so-called 'guide' RNA sequences that lead them to the weapon to its DNA targets. Meanwhile, last month in the UK, a healthy baby was born from an embryo screened for genetic diseases, using karyomapping, a breakthrough testing method that allows doctors to identify about 60 debilitating hereditary disorders.
|The James Webb Telescope|
Excerpt from space.com
A telescope will soon allow astronomers to probe the atmosphere of Earthlike exoplanets for signs of life. To prepare, astronomer Lisa Kaltenegger and her team are modeling the atmospheric fingerprints for hundreds of potential alien worlds. Here's how: The James Webb Space Telescope, set to launch in 2018, will usher a new era in our search for life beyond Earth. With its 6.5-meter mirror, the long-awaited successor to Hubble will be large enough to detect potential biosignatures in the atmosphere of Earthlike planets orbiting nearby stars. And we may soon find a treasure-trove of such worlds. The forthcoming exoplanet hunter TESS (Transiting Exoplanet Survey Satellite), set to launch in 2017, will scout the entire sky for planetary systems close to ours. (The current Kepler mission focuses on more distant stars, between 600 and 3,000 light-years from Earth.)
While TESS will allow for the brief detection of new planets, the larger James Webb will follow up on select candidates and provide clues about their atmospheric composition. But the work will be difficult and require a lot of telescope time. "We're expecting to find thousands of new planets with TESS, so we'll need to select our best targets for follow-up study with the Webb telescope," says Lisa Kaltenegger, an astronomer at Cornell University and co-investigator on the TESS team. To prepare, Kaltenegger and her team at Cornell's Institute for Pale Blue Dots are building a database of atmospheric fingerprints for hundreds of potential alien worlds. The models will then be used as "ID cards" to guide the study of exoplanet atmospheres with the Webb and other future large telescopes. Kaltenegger described her approach in a talk for the NASA Astrobiology Institute's Director Seminar Series last December. "For the first time in human history, we have the technology to find and characterize other worlds," she says. "And there's a lot to learn."
|Astronomer Lisa Kaltenegger |
Detecting life from space In its 1990 flyby of Earth, the Galileo spacecraft took a spectrum of sunlight filtered through our planet's atmosphere. In a 1993 paper in the journal Nature, astronomer Carl Sagan analyzed that data and found a large amount of oxygen together with methane — a telltale sign of life on Earth. These observations established a control experiment for the search of extraterrestrial life by modern spacecraft. "The spectrum of a planet is like a chemical fingerprint," Kaltenegger says. "This gives us the key to explore alien worlds light years away." Current telescopes have picked up the spectra of giant, Jupiter-like exoplanets. But the telescopes are not large enough to do so for smaller, Earth-like worlds. The James Webb telescope will be our first shot at studying the atmospheres of these potentially habitable worlds. Some forthcoming ground-based telescopes — including the Giant Magellan Telescope (GMT), planned for completion in 2020, and the European Extremely Large Telescope (E-ELT), scheduled for first light in 2024 — may also be able to contribute to that task. [The Largest Telescopes on Earth: How They Compare] And with the expected discovery by TESS of thousands of nearby exoplanets, the James Webb and other large telescopes will have plenty of potential targets to study. Another forthcoming planet hunter, the Planetary Transits and Oscillations of stars (PLATO), a planned European Space Agency mission scheduled for launch around 2022-2024, will contribute even more candidates. However, observation time for follow-up studies will be costly and limited. "It will take hundreds of hours of observation to see atmospheric signatures with the Webb telescope," Kaltenegger says. "So we'll have to pick our targets carefully."
Set to see its first light in 2021, The Giant Magellan Telescope will be the world’s largest telescope.
Getting a head start To guide that process, Kaltenegger and her team are putting together a database of atmospheric fingerprints of potential alien worlds. "The models are tools that can teach us how to observe and help us prioritize targets," she says. To start, they have modeled the chemical fingerprint of Earth over geological time. Our planet's atmosphere has evolved over time, with different life forms producing and consuming various gases. These models may give astronomers some insight into a planet's evolutionary stage. Other models take into consideration the effects of a host of factors on the chemical signatures — including water, clouds, atmospheric thickness, geological cycles, brightness of the parent star, and even the presence of different extremophiles. "It's important to do this wide range of modeling right now," Kaltenegger said, "so we're not too startled if we detect something unexpected. A wide parameter space can allow us to figure out if we might have a combination of these environments." She added: "It can also help us refine our modeling as fast as possible, and decide if more measurements are needed while the telescope is still in space. It's basically a stepping-stone, so we don't have to wait until we get our first measurements to understand what we are seeing. Still, we'll likely find things we never thought about in the first place."
A new research center The spectral database is one of the main projects undertaken at the Institute for Pale Blue Dots, a new interdisciplinary research center founded in 2014 by Kaltenegger. The official inauguration will be held on May 9, 2015. "The crux of the institute is the characterization of rocky, Earth-like planets in the habitable zone of nearby stars," Kaltenergger said. "It's a very interdisciplinary effort with people from astronomy, geology, atmospheric modeling, and hopefully biology." She added: "One of the goal is to better understand what makes a planet a life-friendly habitat, and how we can detect that from light years away. We're on the verge of discovering other pale blue dots. And with Sagan's legacy, Cornell University is a really great home for an institute like that."