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Scientists 'edit' DNA to correct adult genes and cure diseases

DNA
© The Independent, UKExperts hail ‘fantastic advance’ of new technique that can alter life-threatening mutations with pinpoint accuracy.
A genetic disease has been cured in living, adult animals for the first time using a revolutionary genome-editing technique that can make the smallest changes to the vast database of the DNA molecule with pinpoint accuracy.

Scientists have used the genome-editing technology to cure adult laboratory mice of an inherited liver disease by correcting a single "letter" of the genetic alphabet which had been mutated in a vital gene involved in liver metabolism.

A similar mutation in the same gene causes the equivalent inherited liver disease in humans - and the successful repair of the genetic defect in laboratory mice raises hopes that the first clinical trials on patients could begin within a few years, scientists said.

The success is the latest achievement in the field of genome editing. This has been transformed by the discovery of Crispr, a technology that allows scientists to make almost any DNA changes at precisely defined points on the chromosomes of animals or plants. Crispr - pronounced "crisper" - was initially discovered in 1987 as an immune defence used by bacteria against invading viruses. Its powerful genome-editing potential in higher animals, including humans, was only fully realised in 2012 and 2013 when scientists showed that it can be combined with a DNA-sniping enzyme called Cas9 and used to edit the human genome.

Since then there has been an explosion of interest in the technology because it is such a simple method of changing the individual letters of the human genome - the 3 billion "base pairs" of the DNA molecule - with an accuracy equivalent to correcting a single misspelt word in a 23-volume encyclopaedia.

Blue Planet

Climate change: Antarctica once as warm as California coast

West Antarctica
© Newcastle UniversityA new temperature measurement technique has revealed Antarctica was once as warm as California.
A study of ancient fossil shells has revealed that the Antarctic was once as warm as the California coast.

Yale University scientists came to their conclusion after trying a different model to gauge historic temperatures.

Their findings underscore the potential for seesawing temperatures at the Earth's poles and the associated risk of melting polar ice and rising sea levels.

Sun

Guide to April 29th solar eclipse

Solar Eclipse_1
© David DickinsonThe 2013 partial eclipse rising over the Vehicle Assembly Building along the Florida Space Coast. This month’s solar eclipse will offer comparable sunset views for eastern Australia.
Will anyone see next week's solar eclipse? On April 29th, an annular solar eclipse occurs over a small D-shaped 500 kilometre wide region of Antarctica.

This will be the second eclipse for 2014 - the first was the April 15th total lunar eclipse - and the first solar eclipse of the year, marking the end of the first eclipse season. 2014 has the minimum number of eclipses possible in one year, with four: two partial solars and two total lunars.

This month's solar eclipse is also a rarity in that it's a non-central eclipse with one limit. That is, the center of the Moon's shadow - known as the antumbra during an annular eclipse - will juuuust miss the Earth and instead pass scant kilometres above the Antarctic continent.

Document

Neanderthals had shallow gene pool

Neanderthal
© Neanderthal Museum (Mettmann, Germany)A girl goes nose-to-nose with a Neanderthal statue in Germany. Ancient DNA research is increasingly revealing the genetic links between modern humans and our extinct ancestors, including Neanderthals and the mysterious Denisovans.
Neanderthals were remarkably less genetically diverse than modern humans, with Neanderthal populations typically smaller and more isolated, researchers say.

Although Neanderthals underwent more genetic changes involving their skeletons, they had fewer such changes in behavior and pigmentation, scientists added.

Modern humans are the only humans alive today, but Earth was once home to a variety of other human lineages. The Neanderthals were once the closest relatives of modern humans, with the common ancestors of modern humans and Neanderthals diverging between 550,000 and 765,000 years ago. Neanderthals and modern humans later interbred - nowadays, about 1.5 to 2.1 percent of DNA of people outside Africa is Neanderthal in origin.

Top Secret

America's newest top-secret spy plane? Mystery aircraft spotted flying over Kansas, Texas

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A mysterious flying object was snapped flying over Wichita, Kansas by Jeff Templin. It resembles a similar unidentified aircraft streaking across the skies of Texas last month.
  • A new image shows a mysterious aircraft flying over Kansas
  • The jet appears to be the same one that was spotted over Texas last month
  • Photographer Jeff Templin says it may have been as high as passenger jets
  • A retired Marine previously said the mysterious plane is the SR-72
  • The SR-72 is designed to cross entire continents in less than an hour
  • Developers at Lockheed Martin say the plane could be operational by 2030
A new photo of a mysterious flying object over Kansas has been revealed.

It appears to be the same aircraft as one that was snapped soaring over Texas last month.

The exact identify of the aircraft remains a mystery, but rumours abound that it could be a secret jet.

Chalkboard

Fracking: Scientific review reveals public health hazards and data gaps

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© Adam Gregor/Shutterstock
Researchers from the scientific organization PSE (Physicians Scientists & Engineers for Healthy Energy), the University of California, Berkeley and Weill Cornell Medical College conducted the first systematic literature review of public health effects and routes of exposure of contaminants associated with shale and tight gas development (i.e., fracking).

The research shows that many of the studies reviewed identified associations between the development of shale and tight gas and elevated levels of toxic compounds in the environment. The researchers note that while the scientific literature on this modern type of natural gas development has grown recently, more epidemiological studies are needed to investigate public health impacts.

The review, "Environmental Public Health Dimensions of Shale and Tight Gas Development" was published online in the peer-reviewed journal, Environmental Health Perspectives on April 16 at 12:01 a.m. Eastern.

Galaxy

Coming soon: The telescope big enough to spot signs of alien life on other planets‏

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An artist's impression of the European Extremely Large Telescope (E-ELT).
Cerro Armazones is a crumbling dome of rock that dominates the parched peaks of the Chilean Coast Range north of Santiago. A couple of old concrete platforms and some rusty pipes, parts of the mountain's old weather station, are the only hints that humans have ever taken an interest in this forbidding, arid place. Even the views look alien, with the surrounding boulder-strewn desert bearing a remarkable resemblance to the landscape of Mars.

Dramatic change is coming to Cerro Armazones, however - for in a few weeks, the 10,000ft mountain is going to have its top knocked off. "We are going to blast it with dynamite and then carry off the rubble," says engineer Gird Hudepohl. "We will take about 80ft off the top of the mountain to create a plateau - and when we have done that, we will build the world's biggest telescope there."

Fireball

The biggest threat to humanity, far bigger than global warming/climate change, is about to get bigger, much bigger

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© UnknownThe chelyabinsk asteroid fireball, a “near-Earth object” (NEO), an asteroid (likely made of rock) between 15 and 20 meters across (about the length of a school bus), which just happened to arrive in the same place as planet Earth that morning. The mass of the object was about 10 thousand tons. It struck the atmosphere moving at about 40,000 MPH (more than double the speed of the Space Shuttle).
A press release from some former NASA astronauts on the current asteroid impact threat to earth, based on data on in-atmosphere detonations since 2001, gleaned from a nuclear weapon detonation detection system has yielded some startling numbers.

The threat is 3 to 10 times higher than previously predicted. The data will be presented at the Seattle Flight Museum, Tuesday April 22, at 6:00pm PDT.

Just last night, another fireball was seen over Russia, caught on a dashcamera. See video.

Document

Turning science on its head: Harvard researchers offer new views of body's insulating material

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© Daniel Berger and Giulio TomassyThe higher you look in the cerebral cortex, the less myelin you'll find, according to Professor Paola Arlotta. Not only that, but “neurons in this part of the brain display a brand-new way of positioning myelin along their axons that has not been previously seen," Arlotta added. Pictured is an image of three neurons.
Harvard neuroscientists have made a discovery that turns 160 years of neuroanatomy on its head.

Myelin, the electrical insulating material in the body long known to be essential for the fast transmission of impulses along the axons of nerve cells, is not as ubiquitous as thought, according to new work led by Professor Paola Arlotta of the Harvard Stem Cell Institute (HSCI) and the University's Department of Stem Cell and Regenerative Biology, in collaboration with Professor Jeff Lichtman of Harvard's Department of Molecular and Cellular Biology.

"Myelin is a relatively recent invention during evolution," says Arlotta. "It's thought that myelin allowed the brain to communicate really fast to the far reaches of the body, and that it has endowed the brain with the capacity to compute higher-level functions."

In fact, loss of myelin is a feature in a number of devastating diseases, including multiple sclerosis and schizophrenia.

But the new research shows that despite myelin's essential roles in the brain, "some of the most evolved, most complex neurons of the nervous system have less myelin than older, more ancestral ones," said Arlotta, co-director of the HSCI neuroscience program.

Bulb

Michael R. Eades, M.D.: Beware the confirmation bias

Recently, while alone and unsupervised, I allowed myself to be goaded into an ill-advised Twitter debate. With someone who calls himself Ducks Dodger, no less. (For those of you who didn't see it, you can go to my Twitter account, scroll back to April 8-9 and check out this tar baby I got caught up in.)

I soon realized the entire affair was an exercise in futility, so extracted myself from it. It was an exercise in futility because it was a blatant case of the confirmation bias writ large. But my aggravation hasn't gone to waste because I've been waiting for an excuse to write a little essay on the confirmation bias that plagues us all. Who knew fate, in the guise of Ducks Dodger, would give me the prod I needed.
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Taktu cleaning fat from seal skin with an ulu
Cape Dorset (Kinngait), Nunavut, Canada, August, 1960
In a bit, I'll describe the details of this Twitter fiasco and how the confirmation bias reared its head. But first, let's look at provoker-in-chief of the confirmation bias: cognitive dissonance.

Comment: More food for thought: The Truth Wears Off.