The Virginia AG’s Attack on Climate Scientists | The Intersection

Tim Lambert has news that deeply troubles me: The state of Virginia's Republican attorney general, Ken Cuccinelli, has launched a fishing expedition investigation into climate researcher Michael Mann's days at the University of Virginia. The request sounds quite massive, according to the Hook:
Among the documents Cuccinelli demands are any and all emailed or written correspondence between or relating to Mann and more than 40 climate scientists, documents supporting any of five applications for the $484,875 in grants, and evidence of any documents that no longer exist along with proof of why, when, and how they were destroyed or disappeared. The request also appears to cover a six year period. This is clearly another attempt to make fire out of the mere smoke that was ClimateGate. But remember, so far, Mann has been vindicated by his university. In this context, I don't see how one can possibly justify putting scientists through such an extensive and burdensome inquiry. There is obviously strong potential for a chilling effect on their research. I am sure this post will prompt a lot of comments--so, be good.....


The Companion Molecule [Science Tattoos] | The Loom

Scicurious caffeine440Scicurious, a blogger at Neurotopia with a PhD in physiology, writes,

The molecule is caffeine, and the tattoo itself was designed by artist Glendon Mellow of The Flying Trilobite. I got it to celebrate my PhD.

Why caffeine, you ask?

1) I had a friend once tell me that my friendship was like a hot cup of coffee. Warm, vivacious, stimulating, and comforting. It was one of the best compliments I ever received.

2) I have spent the last six years of my life studying drugs in various forms. Caffeine always spoke to me as a stimulant, because it is so different from other traditional drugs classified as stimulants. I’ve always been a little different myself.

3) I also spent the past six years studying various neurotransmitters. I will spend more years studying different neurotransmitters. Which ones I study and why will change over time, but caffeine will be with me through all of it. :)

Click here to go to the full Science Tattoo Emporium.


Reflections on “Unruly Democracy” from Bioephemera (Jessica Palmer) | The Intersection

I think I can safely say that our event on Friday at the Harvard Kennedy School, entitled "Unruly Democracy: Science Blogs and the Public Sphere," was a success, and perhaps even exceeded expectations. The room was full; the presentations were great; we had a historic first panel bringing together representatives of Seed, Discover, and The Boston Globe to talk about three different approaches to science blogging; we had a real debate about whether blogs are "good" or "bad" for science--and we had a move towards some constructive suggestions for finding better norms in the blogosphere. If you want proof that the event has caused some very important thought and reflection, you need go no further than this lengthy post from Jessica Palmer of Bioephemera, who attended and gave a rockin' talk on my panel. Jessica is, broadly speaking, in my camp--or what on Friday was called the "Sunsteinian" camp--when it comes to the negatives of blogging. Why? Some excerpts from her post:
My big concern? While individual blogs often have communities who are internally civil and share norms and history, when you move from blog to blog, those norms and history break down. There are no universal norms in the science blogosphere, ...


How the Universe Works | Bad Astronomy

A new science show premiered on The Discovery Channel last week called "How The Universe Works". I just watched the first episode, and it’s pretty good!

howtheuniverseworks

The first show was about the Big Bang, and hits all the right notes. The graphics are pretty good — that’s de rigeur for modern TV shows — but the music is nice, too. The writing is engaging, and Mike Rowe is a terrific narrator. All in all, I recommend it… tonight’s (Sunday) episode is about black holes. I have word that a certain Bad Astronomer is interviewed for that one… and I did a bunch of other topics for them as well, so I assume you’ll be seeing more of me on the show in later episodes, too!


People of class drink alcohol | Gene Expression

don-draperOn his twitter feed one Conor Friedersdorf made a comment about how beer unites people across the ideological spectrum. I raised my eyebrows at this, because I know that a substantial number of Southern white Protestants do not drink alcohol. With a name like Friedersdorf I suspect that Conor probably didn’t consider this because of the normative nature of beer consumption in his social circles. I’ve always meant to look into the differences in alcohol consumption by demographic because I’m sure you’ve seen all the medical “studies” which claim that drinking in moderation has benefits toward your health. The main concern I have is that a lot of these seem to be correlational studies (though not all), and there are also often conflicts of interest with the funding (the alcoholic beverage industry is naturally happy to front the cash to pursue research so as to make the correlation firmer in the public mind). Now, I have nothing against alcohol personally, I like dark beers and white wines. But I’m a little skeptical when people promote health benefits of a class of product with which a non-trivial minority of the population have substance abuse issues.

To sate my curiosity, I decided to look at the GSS. So you can replicate, here are my variables:

Row: Drink

Column: Year Race Sex Region God(r:1-3″Non-theist”;4-5″Believe, But Doubts”;6″Know God Exists”) Relig Polviews Degree Wordsum

Some of the variables are obvious, but in regards to the somewhat garbled gibberishy looking section I “recoded” it so as to combine classes with very small N’s and such. Since you have the variable names you can follow up and see what I did if you’re curious.

Here are some results….

Not too much change over the years.

drinkyear

Now, some demographic variables of interest. Not too surprising. I knew that blacks were more likely to be teetotalers, and expected that women would be as well. Note the big difference by religion.

drinkdemcat

As I said, people in the South are less likely to drink. This partly tracks religion, but I’ve poked around these particular data and in New England both Catholics and Protestants drink a fair amount, so it is a regional Protestant subculture which is fostering teetotaling (here are the labels geographically by the way).

drinkregion

Some more variables, though note the spectrum. The conservative tendency toward teetotaling probably has something to do with the correlates of extreme conservatism (higher religiosity, tendency to live in the South, be Protestant, etc.). Keep an eye on the education though….

drinkideology

This chart pretty much floored me.

drinkwordsum

I was expecting it. That is, that the more intelligent, who scored high on a vocabulary test, would drink more than the dumb, who scored low. Look at the other correlates above. But I’ve rarely seen such a stark near-monotonic trend with Wordsum.

You can try to control for variables. Race doesn’t matter much for what it’s worth, the trends stay pretty much the same if you constrain to whites. I decided to check the “Bible” variable, which measures literal interpretation. As expected controlling for fundamentalism eliminates much of the Protestant vs. non-Protestant difference, as well as exacerbates the sex difference (fundamentalist women are much more teetotaling than men), but it really didn’t effect the rank relation on many categories. The regional and Wordsum difference remains even among those who are fundamentalists or irreligious. I think this points to the social aspect of drinking. Even if you like to drink, if you’re circle of acquaintances tends not to, you won’t get a chance to drink as much. Conversely, if drinking is expected, there’s more pressure to bend your norms to please your friends.

Anyway, just be careful of studies extolling the virtues of alcohol unless they control for confounds. It’s just a fact that stupid people tend to die earlier, because they often make life decisions in keeping with their nature.

Image Credit: AMC

Permission Granted

Released under the GNU Free Documentation License.

AROLSO is the Authorized Return of Overseas Launch Space Object.  This is permission to land the Sample Recovery Capsule aboard JAXA’s Asteroid Explorer “HAYABUSA” in Australia. The authorization came from Australia’s Space Licensing and Safety Office.

HAYABUSA was launched May 9, 2003 and fired up the Ion engine on May 27, 2003 heading for the asteroid Itokawa.  The spacecraft arrived at the asteroid on September 12, 2005.  If getting to the asteroid wasn’t enough, HAYABUSA actually landed on the asteroid twice.  The first landing involved the release of a target marker with some 880,000 names.  The second involved getting a sample of the asteroid!  That sample is due to reach Earth, specifically the Woomera Prohibited Area in South Australia on June 13 at 11 pm Japan Standard Time (I think that’s 2pm ET).

The mission as amazing at it sounds is in my opinion raised to an even higher level of achievement by the way JAXA handled some unplanned glitches that could have ended it.  The JAXA site has an interactive time line of the mission from launch to return, be sure to check it out.

Japan’s “Solar Yacht” Is Ready to Ride Sunbeams Through Space | 80beats

Solar SailOn May 18, the Japan Aerospace Exploration Agency (JAXA) says, it will launch into space a “solar yacht” called Ikaros—the Interplanetary Kite-craft Accelerated by Radiation of the Sun (named, of course, in honor of Icarus in Greek mythology). JAXA plans to control the path of Ikaros by changing the angle at which sunlight particles bounce off the silver-coloured sail [AFP].

Actually, the solar sail is a dual-purpose system, taking advantage of both the pressure and the energy of sunlight. The sail, which is less than the thickness of a human hair and 66 feet in diagonal distance, will catch the actual force of sunlight for propulsion as a sailboat’s sail catches the wind. But the solar sail is also covered in thin-film solar cells to generate electricity. And if you can make electricity, you can use it to ionize gas and emit it at high pressure, which is the propulsion systems most satellites use.

Potential velocity using a solar sailor has been theorized to be extremely high. “Eventually you’ll have these missions lasting many years, reaching speeds approaching 100,000 mph, getting out of the solar system in five years instead of 25 years,” said Louis D. Frieman, the Executive Director of the Planetary Society [Clean Technica]. The society has toyed around with its own solar sail.

For now, though, JAXA has a six-month test mission planned for Ikaros. If it works, they want to send a solar sail-powered mission to Jupiter and then the Trojan asteroids. That voyage would employ both the force of the sun and ion propulsion, and the Japanese are brimming with confidence: “Unlike the mythical Icarus, this Ikaros will not crash,” Yuichi Tsuda, an assistant professor at JAXA, said today [BusinessWeek].

Related Content:
80beats: Japan’s Damaged Asteroid Probe Could Limp Back to Earth in June
80beats: Spacecraft That Sails on Sunshine Aims For Lift-Off in 2010, on the Planetary Society’s own attempts at a solar sail.
DISCOVER: Japan Stakes Its Claim in Space
DISCOVER: One Giant Step for a Small, Crowded Country, on Japan’s moon aspirations
DISCOVER: Japan Sets Sail in Space

Image: JAXA


NCBI ROFL: How to turn your scrapbooking obsession into a dissertation. | Discoblog

Friends for better or for worse: interracial friendship in the United States as seen through wedding party photos. "Friendship patterns are instrumental for testing important hypotheses about assimilation processes and group boundaries. Wedding photos provide an opportunity to directly observe a realistic representation of close interracial friendships and race relations. An analysis of 1,135 wedding party photos and related information shows that whites are especially unlikely to have black friends who are close enough to be in their wedding party. Adjusting for group size, whites and East and Southeast Asians (hereafter E/SE Asians) are equally likely to be in each other's weddings, but whites invite blacks to be in their wedding parties only half as much as blacks invite whites, and E/SE Asians invite blacks only one-fifth as much as blacks invite E/SE Asians. In interracial marriages, both E/SE Asian and black spouses in marriages to whites are significantly less likely than their white spouses to have close friendships with members of their spouse's race." Image: flickr/Bludgeoner86 Related content:
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Dramatic video of NASA balloon accident that destroys payload | Bad Astronomy

This is awful: during the launch of a high-altitude balloon, something went wrong. The balloon dragged the payload across the ground, destroying it, and in the meantime not doing any good to an SUV parked nearby:

This happened yesterday, in Australia. No one was hurt, but the payload apparently was totaled. It looks to me that the balloon got caught by some wind before they were quite ready to launch, and it pulled the payload off the crane. Seeing what it did to that SUV… yikes.

The balloon was carrying gamma-ray detectors as a testbed for a future NASA observatory. Gamma rays don’t penetrate the Earth’s atmosphere, so observatories have to be launched into space. The detectors on-board can be tested on the ground, but at some point need to get up above as much of the atmosphere as possible to see how they do in those conditions and observing actual astronomical sources. Balloons are the easiest and cheapest way to do that.

I know some folks who have done balloon launches like this, and they’ve told me it can be a little hairy. I trusted them, but until I saw that payload smash into and flip over that truck, I didn’t fully realize what they meant. Wow.

This is a setback for NASA and the team building the observatory. I don’t know how much, exactly, but I’m sure it will be months or even years to rebuild this. I can’t imagine much will be salvaged off this disaster.

I saw this earlier today, but no video was available to embed. So thanks to Tom’s Astronomy blog where I saw this, and Discovery News where I first heard about it.


Legendary Giant Earthworm Finally Appears, Disappoints Everybody | 80beats

giant-palouse-earthwormIt’s an earthworm so mysterious, people compare it to the Loch Ness Monster. Rarely sighted since the 1980’s, the giant Palouse earthworm was said to grow almost three feet long, smell like lilies, and spit at predators. It was so elusive, that some even doubted its existence–but now, a team of conservationists from the University of Idaho has found several of these mysterious creatures in a prairie field.

But what a let down it was.

Contrary to popular claim, the earthworms did not smell like lilies or spit at their predators. They weren’t even particularly giant, causing lead researcher Jodi Johnson-Maynard to remark: “One of my colleagues suggested we rename it the ‘larger than average Palouse earthworm’” [The Telegraph].

The team started combing the prairie region between Idaho and Washington state last summer in search of the Palouse earthworms. It was researcher Karl Umiker who eventually struck gold–or in this case, worm. Umiker used a tool called an electroshocker, in which electricity is passed through a number of electrodes that are stuck in the soil. Umiker was “shocking” a fragment of unploughed prairie when two giant earthworms emerged from the soil–a juvenile and an adult.

The Palouse worms were said be abundant in the 19th century, but farming of the prairie land reduced their numbers drastically. The worms were considered extinct until 2005, when Idaho graduate student Yaniria Sanchez-de Leon found a specimen near Albion, Wash. But that worm had been cut nearly in half as she was digging a hole [AP]. It’s not clear whether the worms retrieved last month were part of tiny population of remaining worms, or whether they’re considered rare simply because they live deep in the soil (down to 15 feet below the surface) and flee from the vibrations caused by digging scientists.

When they were extracted from the soil, both worms were about seven inches long. Says Johnson-Maynard: “But when we stretched it out and relaxed it, the adult earthworm got bigger…. It’s between 9 and 10 inches” [The New York Times]. That’s still a far cry from the myth of 3-foot-long Palouse worms. Johnson-Maynard says that legend may have arisen from reports of one truly giant specimen recovered many years ago. “Apparently some boy was swinging it in the air like a rope, and it stretched” [The New York Times].

Johnson-Maynard confirmed that the worms did not smell like lilies either, saying, “I have a fairly sensitive nose, and I just can’t smell the lily” [NPR]. The researchers have also seen no evidence of spitting.

While the adult was killed in order to confirm whether it was indeed a Palouse earthworm, researchers are excited to still have the juvenile alive and in one piece. For now, the captured juvenile is resting comfortably, Dr. Johnson-Maynard said, adding, “We have it in a cooler in soil with ice packs” [The New York Times].

Related Content:
80beats: Worm Has a Spider-Sense Gene That Keeps It Out of Trouble
Discoblog: Worms Are Picky Ejaculators
Discoblog: Worm Grunting Mystery Solved…by Darwin
Discoblog: New “Worm Charming” Champion Sets World Record

Image: University of Idaho


Einstein Should Be Grateful He Didn’t Have Email | Cosmic Variance

I’m reading an interesting new book, Bursts by Albert-Laszlo Barabasi. It’s just released today, but I scored an advance copy by virtue of sharing the same publisher. The basic idea is simple: human behavior obeys power laws! That is, things we occasionally do tend to be clustered together, rather than simply occurring with uniform probability. I can’t vouch for either the truth or usefulness of the claims put forward in the book; we all know that power laws can be slippery things. But the stories related along the way are pretty amusing. (And there’s a very spiffy web page.)

I’ll admit that I jumped right to a chapter in the middle that relates the correspondence between Einstein and Theodor Kaluza in the year 1919 and thereabouts. Kaluza had just come up with the idea that electromagnetism could be unified with gravity by hypothesizing an extra dimension of space — a scenario now known as Kaluza-Klein theory, which underlies all the contemporary excitement about extra dimensions of space. Many crackpots like to assert that our contemporary system of scientific publishing is overly ossified and hierarchical, and that a modern-day Einstein would never be appreciated; the truth is close to the opposite, as back in those days you really needed endorsement from someone established to get your papers published. So Kaluza wrote to Einstein, who was originally enthusiastic about the idea, and they had a flurry of correspondence. Eventually (as I now know) Einstein cooled on the idea, and Kaluza left physics to concentrate on pure mathematics. A couple of years later, after getting nowhere with his own attempts to unify gravity and E&M, Einstein turned back to Kaluza’s approach, and wrote him again, offering to present his paper to the academy.

The book’s interest is actually in the “burstiness” of the correspondence — a flurry of letters back and forth in 1919, then silence, then the conversation resumed in 1921. I was struck by this paragraph, relating the growth of Einstein’s celebrity after the eclipse expedition of 1919 provided evidence supporting general relativity.

[Einstein's] sudden fame had drastic consequences for his correspondence. In 1919, he received 252 letters and wrote 239, his life still in its subcritical phase, allowing him to reply to most letters with little delay. The next year he wrote many more letters than in any previous year. To the flood of 519 he received, we have record of his having managed to respond to 331 of them, a pace, though formidable, insufficient to keeping on top of his vast correspondence. By 1920 Einstein had moved into the supercritical regime, and he never recovered. The peak came in 1953, two years before his death, when he received 832 letters and responded to 476 of them.

Can you imagine what Einstein would have faced in the email era? One thing is for sure: he was a champion correspondent. He composed approximately 14,500 letters, more than one per day over the course of his adult life.

Not for the first time, Einstein makes me feel like a slacker.


Monsters from the Id! | Bad Astronomy

If you’re in LA this weekend, and you love SciFi and mad scientists — and c’mon, who doesn’t? — then you’ll want to attend the screening of "Monsters from the Id", a documentary on mad scientists, 1950s movies, and the future of science in the US. Seriously, check this video out and tell me you don’t want to see this:

There will be a panel after the screening, talking about these topics as well. That trailer hits all the right notes, and features some of my favorite movies of all time ("War of the Worlds", "Them!", "The Day the Earth Stood Still", "The Thing from Another World", "Forbidden Planet", und so weiter). Man, I wish I could go, but I don’t think I can make it. But don’t let that stop you. Put down the Krell brain enhancing machine and get moving!


A Stupid Way to Get Electricity for Free: Meat Hook + Power Line | Discoblog

Having the power shut off in your home due to lack of payments can really motivate you to pay your bills—or perhaps to begin siphoning electricity with a meat hook. A recent report from Reuters describes a middle-aged man in Germany who has been stealing electricity from a high-voltage overhead transmission line using a run-of-the-mill meat hook. After getting cut off by the power company for not paying his bills, the energy thief decided he would acquire the necessary power on his own; he attached a meat hook to the end of a long cable, and hurled the hook onto an overhead power line 150 meters from his house. By routing some of the electricity to his meter box, the man powered his home illegally for an entire month before anyone noticed. Now before you run off to Home Depot to buy cable and meat hooks (do they sell meat hooks at Home Depot?), you should be aware that siphoning electricity is not only illegal, it's also insanely dangerous. A report from the Australian Broadcasting Corporation noted the recent death of a man who was electrocuted from trying to siphon off power for an illegal drug lab. And utility employee Friedrich-Wilhelm Lach ...


Armageddon delayed by at least a century… this time | Bad Astronomy

What does a one-in-ten-million chance of apocalypse look like? Well, it used to look like this:

2005yu55

That is asteroid 2005 YU55, a near-Earth object (or NEO) that also happens to be a PHA, or potentially hazardous asteroid. It has an orbit which intersects the Earth, which means that someday it could possibly hit us.

Now before you panic — and I’ll make this clear: DON’T PANIC — that doesn’t mean you’ll wake up tomorrow to see flaming death streaking across the sky. Think of it this way: when you walk to the local convenience store to get a squishy, you have to cross the street. The path you take intersects the street, but as long as you don’t try to occupy the same spot as a moving car, you won’t get hit. Same with PHAs: their orbits cross the Earth’s orbit, but space is big. As long as the Earth and the asteroid aren’t at the same place at the same time, we’re OK.

Since we don’t know the orbits of these objects perfectly, we assign a probability they will hit us over some period of time. Up until recently, YU55’s chance of hitting us over the next century was calculated to be about 1 in 10,000,000, which is reasonably close enough to 0 for me. However, it’s always good to get better data. In this case, very good: new observations have eliminated the chance that YU55 will ruin our day for at least a century to come.

YU55 was observed with the monster 300 meter (1000 foot) Arecibo radio telescope in Puerto Rico. Arecibo can send little radar pings into space, aimed at an asteroid. The pings reflect off the rock, come back to Earth, and the timing of each one can be logged. This tells us how far away the asteroid is, how big it is, and even (by carefully measuring the different arrival times of the pings back on Earth) the shape of the asteroid.

If this sounds familiar, that’s because this is how dolphins and bats sense their environment. They use sound, not light, but the principle is the same. So what did Arecibo tell us when it dolphinated YU55?

The good news is that the orbit of the asteroid was nailed down better, and that 1 in 10,000,000 chance of an impact in the next century dropped to 0. Nada. Nil. And astronomers are so confident of that they removed YU55 from their Risk Page.

So we’re safe from YU55 ruining our day for quite some time at least.

And that’s good, because, as it turns out, YU55 is bigger than expected: about 400 meters (a quarter mile) across, twice as large as previous estimates showed! Something that big hitting us at orbital speeds would explode with the force of a lot of nuclear weapons — a few thousand megatons, or a hundred times the yield of the largest bomb ever detonated.

So yeah, yay! It won’t hit us, and that’s by any definition good.

But the middlin’ bad news is that this also means is that it’s tough to get good size estimates for asteroids without this technique. Usually, the size of a rock is determined by measuring how bright it is. A bigger asteroid reflects more light, and by measuring how well it reflects sunlight we can estimate the size. But that doesn’t always work so well, as YU55 is telling us. Clearly, we need to use multiple methods to get the sizes of these guys.

Arecibo’s funding is constantly under attack, yet it’s the best machine we have to get the sizes of and, more importantly, accurate orbits for these potentially life-threatening objects. YU55 is off the list now, but there’s a long line of rocks ready and waiting to take its place there.


Need to Find the Big Dipper? There’s an App for That | Discoblog

There used to be a time when you could easily impress a date by pointing to the night sky and dreamily rattling off names of major stars, constellations, and the like. Now, instead of cramming your head full of names or making up stuff as you go along, you can use your trusty iPhone to guide you through your stargazing. There are a bunch of apps that you can download, depending on your interest level and degree of expertise. Most of the apps are based on augmented reality--so all you have to do is point your phone towards the sky and the app does the rest. If you're a beginner, Pocket Universe ($3) and Star Walk ($3) are recommended by The New York Times for iPhone users; while Google Sky Map is great for Android users. With Pocket Universe, you can use the camera view to look at the evening or morning sky, and the app will overlay the labeled view over the real sky. (The iPhone's camera isn't good enough yet to pull off this feat with a dark night's sky.) The app also plots the position of the sun, moon, and planets, displays 10,000 stars, and traces the shapes of the ...


A single genetic fault makes one hand mirror the other’s movements | Not Exactly Rocket Science

FistsClench your left hand into a fist. What happened to your right hand when you did it?

If you’re like most people, the answer is nothing. But, surprisingly, not everyone can do this. Some people make “mirror movements”, where moving one side of the body, particularly the hands, causes the other to move unintentionally. Clench the left fist, and the right one closes too. Doing things like playing the piano or typing are very difficult. In 2002, a Chinese man with the disorder failed to get into the military because he couldn’t use the monkey bars.

Young children sometimes make mirror movements but they almost always grow out of it by the age of 10. The only exceptions tend to be people with rare genetic disorders of the nervous system, like Klippel-Feil and Kallmann syndromes. Now, Myriam Srour from the University of Montreal has found that a single faulty gene can cause the condition.

She studied a large French Canadian family with four generations of members who had been making mirror movements from birth. Not everyone was affected, and the pattern of the disorder strongly suggested that a single dominant genetic fault was responsible. Srour tracked it down by comparing the genomes of affected and normal family members, and her search led her to a short area on the 18th chromosome, which contained three genes.

One of these genes is called DCC and it turned out to be the true culprit behind the disorder. In the Canadia family, those who make mirror movements have a version of DCC with a single altered DNA ‘letter’. This tiny fault means that the protein encoded by DCC is manufactured with a missing chunk. That chunk happens to include many of the most important segments of the DCC protein, which, in its abridged form, is completely useless.

Srour found this mutation in every case of mirror movements, and never in 760 unrelated people whose left and right sides are typically independent. To confirm DCC’s role, she turned to an Iranian family, many of who also demonstrated the quirk from birth. She sequenced their DCC genes and again, she found that those who make mirror movements had broken copies. In this case, the mutation was different but the result was the same – a shortened and ineffectual protein.

It’s not just humans who are affected in this way. If mice have mutated and shortened copies of DCC, they too show mirror movements and they move with a distinctive hopping gait. These strains are affectionately known as Kanga mice. If they lack any copies of the gene entirely, their problems are more severe. The gap between the brain’s hemispheres doesn’t develop properly and the fibres that connect the two halves– the corpus callosum – are fewer in number and misrouted.

These mutant mice hint at DCC’s role. The DCC protein is a docking bay (a receptor) for another protein called netrin-1, whose role is to guide the neurons of the developing nervous system across the midline of the body. Its name even comes from the Sanskrit word “netr”, meaning “one who guides”. But this neural shepherd can’t stick to broken DCC proteins and without its good work, the neuronal connections between the body’s two halves don’t form properly.

Reference: Science http://dx.doi.org/10.1126/science.1186463

More on genetic disorders:

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