2013: The Best of the Best

Top 10 Science Stories of 2013

RealClearScience, 12/13

Last week, we published the 10 biggest junk science stories of 2013.

Now, we turn our attention to the jawdropping, stop-the-presses sort of news that occurred in 2013. In 2012, the discovery of the Higgs boson was such a monumental accomplishment that it resulted in a Nobel Prize. It remains to be seen if any of this year's research will attain that level of recognition, but it is safe to say that 2013 produced some very significant leaps forward in science, particularly in the area of biology.

Read on for RealClearScience's Top 10 science stories of 2013.

10.  MERS Virus Tracked Down

In 1900, the top three causes of death in the U.S. (influenza/pneumonia, tuberculosis and gastrointestinal infections) were due to microbes. Today, the top three causes of death (heart disease, cancer, and chronic lower respiratory disease) are largely due to genetics or lifestyle choices. Thanks to modern science, infectious disease isn't something the developed world has to think about very much.

Yet, every once in a while, a new microorganism pops up somewhere in the world, perhaps just to remind us that they are still relevant. Recently, a deadly pathogen called Middle East Respiratory Syndrome Coronavirus (MERS-CoV) waltzed its way onto the global stage. The first victims died in April 2012. By November 2013 -- just 19 months later -- molecular biologists and epidemiologists had sequenced the virus' genome and even predicted which animals were likely to carry it. (Bats and camels were fingered, and both were eventually found guilty.) The bat-to-camel-to-human link still hasn't been definitively proven, but epidemiologists suspect this was the route of transmission.

The speed with which today's scientists can track down a never-before-seen pathogen is truly astonishing. It's nothing short of a modern-day miracle, yet it's something we all take completely for granted.

9.    Death of Comet ISON

Comet ISON was billed as the "Comet of the Century." As it made its journey around the sun, the giant ball of ice was supposed to glow brighter than the moon, putting on a rare celestial show for all of us Earthlings. Alas, things didn't quite work out as astronomers hoped. The sun had a different plan for Comet ISON: Death. Although a little fragment of the 4.5-billion-year-old comet survived, most of it disintegrated in the blazing heat.

Not all was lost, however. Astronomers have plenty of data to study for years to come.

8.    Some Human Ancestors Didn't Exist?

The trouble with digging around in the dirt for fossils is that telling them apart can be difficult. Take dinosaurs, for instance. Some paleontologists believe that the skulls thought to belong to Triceratops are nothing more than the juvenile version of skulls that really ought to be classified as belonging to Torosaurus.

A similar controversy is now brewing for anthropologists and others who study human evolution. A new skull discovered in the nation of Georgia suggests that Homo habilis, Homo rudolfensis and Homo erectus were actually just one species, not three. Obviously, this is a controversial claim. But if it ends up being verified, it would shake up the human evolutionary tree.

7. Storing Data in DNA

DNA is an information carrying molecule. Naturally, it encodes proteins and functional RNAs, but humans have hijacked it for other purposes. In Txchnologist, Charles Choi wrote about truly amazing research published in the journal Nature:

Researchers working to store information in the form of DNA say they have developed a way to hold an MP3 file containing 26 seconds of Dr. Martin Luther King Jr.'s "I Have a Dream" speech, the text of all 154 of Shakespeare's sonnets, Watson and Crick's seminal paper on the molecular structure of nucleic acids and an image file on a piece of the material the size of a tiny dust particle.

However, synthesizing and reading DNA is a nontrivial matter. As a result, DNA is probably more amenable to long-term data storage. So, don't expect DNA-based USB memory sticks anytime soon.

6.    Supreme Court Rejects Gene Patents

Until this year, it was perfectly legal for a company to patent a DNA sequence. Myriad Genetics, which developed a genetic test for breast cancer, owned patents covering the BRCA1 and BRCA2 gene sequences. (Mutations in these genes are linked to breast cancer.) The effect of these patents was to eliminate all competition from the marketplace; nobody other than Myriad could create a genetic test that relied on those gene sequences. The Association for Molecular Pathology sued Myriad, and the case made its way to the U.S. Supreme Court. In June, the Court unanimously struck down gene patents.

Yet, the decision was scientifically bizarre. The justices wrote that cDNA -- which is essentially RNA converted back to a DNA form -- could still be patented. From a biological perspective, this makes no sense. Messenger RNA, which carries protein-building instructions from DNA, contains the same information as cDNA. However, while the former cannot be patented, the latter can be. Confusion reigns. Until this very important point is clarified, the legal issues surrounding gene patents will likely remain unresolved.

5.    The CRISPR Revolution

Bacteria have immune systems, too. Just like our immune system, bacteria can "remember" viruses that have infected them in the past, thus readying them for future assaults. Though this system, known as CRISPR, serves the same general purpose as its human equivalent, mechanistically it is quite distinct. Instead of recognizing protein antigens, CRISPR targets and destroys specific DNA sequences using matching RNAs.

For molecular biologists, this was a serendipitous discovery. As it turns out, it is quite easy to manipulate the CRISPR system in the laboratory. All they have to do is swap out the RNA for another one that is far more useful -- say, an RNA that targets a gene found in humans or crops. When deployed in other organisms, the tweaked CRISPR system can be used to modify or manipulate genes, far quicker and more efficiently than with traditional methods.

Research in the field has exploded. It is quite possible that a new revolution is brewing in molecular biology.

Source: Elizabeth Pennisi. "The CRISPR Craze." Science 341 (6148): 833-836. 23-August-2013. DOI: 10.1126/science.341.6148.833

4.    Life on Mars: Good News & Bad News

The question of whether or not there is life on Mars has fascinated us for decades. It was largely for this reason that NASA sent the Curiosity rover to the Red Planet. And in May, researchers published a report in Science that Curiosity had found physical evidence that water once flowed on the surface of Mars. Water is required for life as we know it, so the discovery means it is possible that Mars was hospitable to life long ago.

That's the good news. But, Curiosity also dealt up some bad news: There is no detectable methane on Mars. Methane is made by microbes, and it is considered something of a marker for life. The fact that Mars has little (if any) methane indicates that there is probably no microbial activity on the planet. No microbes, no life.

The search, of course, will continue...

3.    Life Found in Subglacial Antarctic Lakes

There are very few places on Earth in which life will not thrive. Extremophiles, by definition, love to set up homes in the most inhospitable places imaginable. The latest strange place now known to harbor life is Lake Vostok -- a dark, frigid body of water in Antarctica that has been buried beneath a couple miles of ice for several million years. And it's not the only one. Lake Whillans and Lake Hodgson, also subglacial Antarctic lakes, are likewise full of life. Intriguingly, the environment on the Jovian moon Europa is similar to these lakes. Could life persist there as well?

2.    The Chelyabinsk Meteor

There's a lot of stuff floating around in space. It is estimated that about 100-300 metric tons of cosmic dust enter Earth's atmosphere every single day. Particles larger than 2 millimeters in diameter create "shooting stars," but most of these microscopic crumbs arrive relatively unnoticed.

But some celestial objects make a more grand entrance. The Chelyabinsk meteor blazed across the Russian sky on February 15, releasing the energy of 30 Hiroshima bombs in an episode the likes of which Earth hasn't witnessed since the Tunguska Event of 1908, which -- incidentally -- also happened in Russia. The shockwave damaged buildings, and resulted in injuries to over a thousand people.

Because of widespread chaos and corruption on Russia's highways, many motorists equip their vehicles with video cameras. Thanks to them, the world got to see excellent footage of the Chelyabinsk meteor.

1.    Human Embryos Cloned

The #1 science story of 2013 is a possible Nobel Prize contender. For the first time, scientists at Oregon Health & Science University cloned human embryos.

You may be wondering why this is such a tremendous advance. After all, scientists have already cloned a whole bunch of animals -- from sheep and goats to dogs and horses. The typical method is known as "somatic cell nuclear transfer" (SCNT), in which a cell nucleus is transplanted into an egg whose nucleus has been removed. However, this technique has never successfully produced a cloned primate; the closest it has gotten is the creation of cloned monkey embryos.

But this year, the same team of scientists that cloned monkey embryos has successfully cloned human embryos and, from them, derived embryonic stem cells. Interestingly, for the technique to work, they had to add just a dash of caffeine.

For those fearful of a dystopian future, cloning human embryos is the first step toward creating a powerful, evil army of space warriors. The rest of us, however, are looking forward to the time when doctors will be able to clone replacement organs.

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