When you think of silicon (Si), you may think about Silicon Valley and the fact that modern computing would not be possible without this element in computer circuits. You may also think about how silicon is the second most abundant element in the Earth's crust, after oxygen. You even see it (or don't see it) every time you look through a piece of glass.

What you probably won't think about are diatoms: tiny photosynthesizing algae that are the primary movers of silicon in the world's oceans. Diatoms depend on silicon. They flock to locations where silicon is available. In the process, they generate enormous blue-green blooms.

A bird's eye view of diatom blooms in the ocean. Credit: Norman Kuring/NASA Ocean Color Group, via NASA Earth Observatory.

Every year, diatoms use almost seven trillion kilograms of silicon. They collect silicon in the form of silicic acid--that's silicon plus four hydrogen atoms and four oxygen atoms--and convert it into silica, the primary constituent of glass. What could algae possibly be doing with all of this amorphous, natural glass?

Diatoms use silica to create protective cell walls called frustules that are strong and chemically inert. Essentially, this is glass armor--cheap glass armor. It costs a diatom only two percent of its total energy budget needed for growth to make its shell.

Their beautifully geometric and symmetric shells are tiny marvels of natural art. Furthermore, each of the estimated 100,000 of species of diatoms has its own unique glass shell design. Diatoms are extremely efficient micro- and nano-architects. They consistently create the same 3D structure over and over again.

A collection of various diatom species. Credit: Wipeter, via the Wikimedia Commons.

The intricate armor protects the diatoms and also acts as a chamber that helps the diatoms photosynthesize by boosting their surface area, facilitating the exchange of gasses between the air, seawater, and organism. The silica in the glass also speeds up the conversion of ocean bicarbonate to carbon dioxide by changing the acidity of the water, which facilitates the exchange of protons in vital chemical reactions. The diatom then uses this carbon dioxide for photosynthesis. Thanks to silicon, diatoms have been able to carve out a unique biological niche in Earth's oceans.

With such efficient photosynthesis thanks to their miniature greenhouses (silica shells), diatoms produce about one quarter of the world's oxygen--almost as much as all tropical forests combined. This process also removes great amounts of carbon dioxide from the atmosphere, potentially helping combat global warming. When diatoms die, their heavy shells cause them to sink down to the depths of the ocean, taking that carbon with them. So, not only do they play a vital role in the global silicon cycle, they are also responsible for removing carbon dioxide and producing the oxygen that we breath.

Since they have been using silicon for more than 110 million years, diatoms are a vital part of Earth's biogeochemical silicon cycle. Diatoms are the world's way of moving silicon between rocks, water, and life. They are a form of life that changes the chemistry of the world's oceans.

In a beautiful cycle, the tiny glass masterpieces created by living diatoms sink to watery depths when the diatom dies. Many of the silica shells become part of the rock record when they fall to a seabed. Over time, these rocks dissolve and become orthosilicic acid, which is reused by new diatoms. These rocks also erode and the old silica shells end up on beachy shores in the form of sand. For 5,500 years, humans have been making glass from the same sand that all came from diatoms.

It's final exam season again, and for students across the country, the midnight oil is burning bright. Yet a question looms: It's the morning after an intense all-night cram session, and there's a little bit of time before that big test. Should you take a short nap? Or is it better to just stay up? I decided to ask Dr. Christopher Landrigan, Director of the Sleep and Patient Safety Program at Brigham and Women's Hospital.

For more with Dr. Landrigan on the science of sleep and sleep deprivation, check out the Q&A below.

NOVA: How did you get interested in studying sleep deprivation?

Landrigan: My interest in patient safety and sleep deprivation began in my own training as a resident at Children's Hospital. Fifteen years ago, there were no limits on how much doctors in training could work, and I often found myself at the tail end of a 36 hour shift, not performing my best. I got interested in this later. Was there an impact this might have on the safety of our patients?

NOVA: Why do we feel sleepy?

Landrigan: There are a number of different factors that drive human alertness and performance. The first is something called the sleep homeostat. It's a seesaw system: The longer you've been asleep, the greater the drive to wake up, and the longer you've been awake, the greater the drive to sleep. There's also the circadian system, a 24 hour biological clock that tends to drive maximum performance in the daytime, and drives maximum sleepiness in the early hours of the morning. If we stay up past the point where our bodies are telling us to go to sleep, then the sleep homeostat system and the circadian system both start working together to force you to go to sleep.

NOVA: What happens when you don't sleep?

Landrigan: We know that reaction time goes down, that your ability to put together complex puzzles in your mind, even to do simple math seems to deteriorate. It's not exactly understood how sleepiness contributes to degradation of cognitive function, but we know from imaging studies that the ability of the brain to metabolize glucose, to do what it's supposed to do, tends to decrease after you've been up too many hours in a row.

There have been a number of studies that have tried to look at the effects of sleep deprivation on performance and compare those to the effect that's induced by alcohol. It's been consistently shown that wakefulness of about 17-20 consecutive hours leads to performance decrements that are more or less equivalent to those induced by a BAC [blood alcohol content] of 0.05. And at the 24 hour mark, on average we will perform as if we had a BAC of 0.1, which is beyond the legal limit. With sleep inertia, sometimes the sleep decrements can be even greater than that 24 hour level.

NOVA: What's sleep inertia?

Landrigan: It's a slowness in the brain, an inability to react as quickly or to perform cognitive functions as well in the first few minutes after awakening. Sleep inertia is really the idea that the brain doesn't go from zero to 60 in six seconds. In fact it can take many minutes to even a couple hours for it to wear off.

If somebody is sleep deprived on a regular basis, there's a tendency to go into a deeper stage of sleep more quickly, and when woken from deeper stages of sleep, it appears that sleep inertia is most profound. So if you are sleep deprived and you're rapidly woken from sleep for whatever reason, the tendency to have sleep inertia where performance is really impaired for a long period of time is at its worst.

NOVA: What's so bad about not getting enough sleep?

Landrigan: We're only beginning to understand what the adverse consequences of this may be. From long term studies, it's pretty clear that not only do performance failures increase after sleep depriving ourselves, but there's a really a very substantially increased risk of safety problems--for drivers, for people in high risk occupations in risky industries, as well as long term health consequences of this sort of thing. We know that people who deprive themselves of sleep or work shift work on a regular basis are at higher risk of diabetes, metabolic syndrome, heart disease, hypertension, obesity, and so on for years to come.

To the extent that one can, thinking a little bit constructively about schedules and planning a little bit ahead to minimize all nights and minimize sleep deprivation. It's going to do you a world of good down the road.

Today I made hydrogen. I followed it up with some helium and a little carbon and oxygen. Tomorrow, if I have a little time on my hands, maybe I'll try for einsteinium.

No, I'm not doing tabletop fusion here at NOVA. I'm using NOVA's new iPad app, "NOVA Elements," which lets you create your own atoms and combine them to make the molecules in everything from a cup of coffee to a wristwatch. It's our first app for iPad and--though I may be a bit biased--I think it's very cool. Angry Birds cool. Complete double rainbow cool. Making your own atoms cool.

The app also includes an interactive periodic table loaded up with facts about each element--when it was discovered, what it looks like, where you'll find it in everyday (and not so everyday) objects--and video clips from "Hunting the Elements," our two-hour special about the periodic table. You can also watch the entire show through the app.

Just remember to turn on the sound: You will definitely want to hear those little Pew! Pew! Pew! sounds that the electrons, neutrons, and protons make as you fire them into your brand new atom. And you'll hear David Pogue, the host of the show and the face and voice of the app, guiding you through the menus and offering encouragement, kudos, and some tough-love commentary as you create your own atoms and molecules.

The app is totally free, and you can download it from the iTunes app store.

Have fun, and let us know what you think!

Muster drill: The drill is at 4:30 p.m. on day one, before we leave port. Crewmembers are outfitted in bright yellow vests and hold signs that point passengers in the right direction. The room key (which also serves as an onboard credit card and ID) has each passenger's muster station assignment clearly printed on it. Each passenger (including our infant niece) gets one; we are instructed to carry them everywhere.

Digital roll call at muster station: Arriving at our muster station, our room keys are scanned, checking us in. We're told to sit down in a particular location (a certain section of the small theater) and wait for further instruction. This is how it would happen in a real emergency. The staff are all knowledgeable and professional. A movie then plays (in English, but with instructions on how to obtain it in Spanish, French, Portuguese, German, and a few other languages) showing us how we will be alerted to an emergency, and how we should proceed. Also, a TV channel constantly showed the safety movie--in case there was nothing good on TV?

Safety instructions are posted in every room: The boat is so large that it's easy to get lost, so the instructions are helpful. During the muster drill, crewmembers are all over the ship holding up signs and pointing passengers in the correct direction. Because there are so many passengers, our muster station isn't actually at our lifeboat, but rather a designated meeting place where we would await further instruction, and be guided to our lifeboat if necessary. We also don't have lifejackets in our stateroom--if needed, we would receive them at our muster station. Our stateroom was on Deck 10--pretty far above the surface of the water--so it would make sense not to have lifejackets in our rooms. Unless they came equipped with parachutes...

Lifeboats: The lifeboats seat 370 people, and there are 18 of them on the ship. They even have bathrooms! If you do the math: 18 lifeboats x 370 passengers = 6,660 seats. Well, the ship holds more than 6000 passengers and 2500-plus crew, so the numbers don't quite add up.

Good things come in small packages: The difference is made up by the expandable life rafts held inside these plastic cylinders. But getting into them is not for the faint of heart. Here's why.

Just slide down the esophagus: Officially it's called the VIKING Evacuation Dual Chute, but we call it "the esophagus." We think you'll see why when you look at the diagram below, which is posted near the expandable rafts. The entrance point is on Deck 4. The exit point is water level (Deck 1). We're quite relieved that we don't practice using these devices at any point, although I guess that some people would find it fun. Probably the same people who think that the zip-line across the back of the ship is fun. Unfortunately, they don't ask you if you are afraid of heights before assigning muster stations and life rafts.

The Esophagus: Here are diagrams showing the "esophagus" in action. It's important not to wear high heels in the esophagus. Could make the trip a bit shorter. (We're relieved to learn that our muster station has us assigned to a "real" lifeboat.)

Crew drill: On the second day of our trip, there is a drill for the crew. Over the ship's PA system, we hear "Bravo Bravo Bravo" and a location. This is code for a fire drill. Crewmembers in full fire-fighting gear head off toward the location announced. The ship's many water-tight doors seal. When the drill is over, the crewmembers let us take their photo. Bravo (fire) team members have red tags on their IDs; EMS-type team members have blue tags. (Our waiter had a blue tag.) The full muster drill we went through is done prior to each sail. There is an all-hands drill once every 2 weeks. On the intervening weeks, the crew is split into half, with the halves alternating drill weeks. The Bravo team practices weekly.

We went to the New Mexico desert to blow up a car. It was an ugly car--a white 1970s Cadillac, rescued from the junkyard. In the trunk, 300 pounds of ammonium nitrate and fuel oil, the same lethal ingredients that the Oklahoma City Bomber used to destroy the Federal Building in 1995. Our car bomb, we were told, would vaporize sections of the Cadillac and level the modular building standing next to it. And our explosives were just one 15th the size of the bomb in Oklahoma City.

This was one of our most anticipated shoots for our two-hour NOVA special, "Hunting the Elements"--and also one of the most horrifying. We had stepped into a virtual terrorist's playground--the Energetic Materials Research and Testing Center at New Mexico Tech--and our morbid curiosity grew with each demonstration. Here, bomb experts and scientists spent their days teaching emergency personnel how to respond to nightmare scenarios, and the daily menu of demos was extensive. For an appetizer, a briefcase bomb that blew the torso off a wooden dummy and a pipe bomb that obliterated a watermelon and the table it was sitting on. For the main course, a letter bomb that amputated and wedged a mannequin's foot in the ceiling and a wooden dummy suicide bomber whose improvised explosive device shot bolts through metal signs like bullets.

We filmed all four explosions with a special high-speed camera that played back the action in eerie slow-motion detail. But it was the dessert course--the grand finale car bomb--that most horrified...and fascinated...our crew. As we watched the playback of the slow-mo footage, a dome of super-heated gas--invisible in real time--appeared above the initial fiery blast, and with each frame, moved up and outwards, warping our view of the desert behind it into a wavy, trippy landscape. "That's the shock wave," one of the bomb technicians said, pointing to the gaseous dome. It's not just the heat and debris from the bomb that'll kill you, he told us. It's the shock wave that'll knock you dead.

Suddenly everyone on the crew wanted to rewind the video. It's not that we'd never heard of a shock wave--most people can tell you it's a wave of energy released when you set off a bomb, literal or otherwise (as in...your dad's reaction to the sentence, "I just totaled the car..."). But few of us realized this was the primary source of destruction. When most of us non-scientists think of bombs, we think of the fiery blast and the lethal projectiles it sends shooting into the air. We were riveted as the ordinance technician described this dome of energy that expanded too quickly to see with the naked eye. "Often, we find victims on the scene who've died without a scratch on them," he explained. They might escape the fire, but a shock wave can literally liquefy their insides.

Now the room was alive with questions: What exactly was a shock wave? How did it work? And why did some chemical reactions create them, while others just caused a fire?

Turns out the answers lie not just in chemistry, but in physics.

Chemistry tells us how fire works. When you strike a match or introduce energy from any heat source (like friction or lightning) to a fuel (like wood or gasoline), carbon atoms in the fuel combine with the oxygen in the atmosphere. In other words, they "oxidize," or burn.

This is how explosives work too. The only difference is the speed of the reaction. Fire needs oxygen to burn, but it has to forage for it in the atmosphere. But a substance like gunpowder, for instance, packs its own oxygen. When ignited, the fuel molecules recombine with oxygen, just as they do with fire--only much more quickly since the oxygen is right there, more available. Instead of the sizzle of a flame, when a gun fires, you hear a bang. That bang is the calling card of an explosion...and it's caused...by a shock wave.

Speed up the reaction even further, however, and the shock wave becomes incredibly destructive. Gunpowder is a relatively slow explosive and its destruction is fairly limited. That's why you can shoot a bullet out of a gun without destroying the barrel. But a high explosive like the ammonium nitrate fuel oil bomb in the car trunk can deliver mass calamity in an instant. Made of unstable molecules with incredible amounts of stored-up energy, these compounds react instantaneously, liberating all that energy in the form of a high-pressure wave traveling at supersonic speeds. According to scientists at New Mexico Tech, in just billionths of a second, a shock wave can produce pressure up to 500,000 times the earth's atmosphere, can travel as fast as six miles per second, and can heat the air to more than 9,000 degrees Fahrenheit.

With power like that, the shock wave pushes away everything in its path, from buildings to bodies--often without even breaking skin. This is where we can really see the role of physics. Think of how crushing a soda can displaces the liquid or air inside it. Our bodies are filled with air-containing organs (lungs, intestines, eardrums) that crush, distort, and tear under the sudden pressure of a blast. There may be no penetrating injury from debris or shrapnel, but victims may hemorrhage with massive internal bleeding.

A shock wave even displaces the air particles in the atmosphere. And this fact, the technician told us, generates the bomb's second lethal force. When the shock wave pushes away the air surrounding the detonation site, it creates a vacuum that sucks air particles and debris back towards the bomb site. When you see glass inside a structure after a bomb attack, the technician said, people tend to think the bomb detonated from outside. It's a common error. Often, the glass was just sucked back in by the vacuum created by the shock wave.

When we inspected the briefcase bomb site after detonation--the charred wooden half-torso sitting in front of the remnants of a desk in a modular building--sure enough, there was glass inside the structure from the windows shattered in the blast. An hour later, after detonating the car packed with explosives parked in front of the structure, the entire building lay in pieces on the ground. Standing miles away in a bunker, we felt a grand rush of adrenaline, followed by a mix of horror both at the destruction and our own fascination with it. These were some of the most devastating--and exciting--reactions chemistry had to offer, and as horrified as we were, we wanted to slow them down and watch them again. Not just to see the wreckage wrought by explosives, but to marvel at the invisible force that wrecked it all in the first place.

"Hunting the Elements" premieres Wednesday, April 4 at 9 p.m. ET on most PBS stations. Please check your local listings to confirm when it will air near you.

Theodore Gray's mad scientist lair sits hidden amidst miles of cornfields outside the small college town of Champaign, Illinois. If you drive by too quickly, you'll miss the entrance, an unmarked gravel driveway off an unnamed country road. Turn in, and where you'd expect to see a quaint farmhouse at the end of the driveway, you'll find an industrial-size hangar filled with a 10-year-old-boy's fantasy toys: model rocket kits, mechanical gizmos, rusting antique farm machinery, and jars marked with skulls and crossbones.

The perfect spot for a mad scientist's lair.

The Lair, as Theo calls it, was one of the last stops on our three-month NOVA film shoot for "Hunting the Elements," a two-hour special about chemistry's famous periodic table. Our crew had been crisscrossing the country and had even traveled to Russia, and we'd dropped our host, New York Times technology columnist David Pogue, into some of the most dramatic scenarios we could find: a tank of sharks that would (hopefully) be repelled by rare earth metals; a firework testing range, where explosions colored by strontium, copper, and barium were launched amidst a pelting Nor'easter; a desolate stretch of the New Mexico desert, where we blew up a Cadillac Deville with 300 pounds of ammonium nitrate and fuel oil.

Each of these places revealed details about specific elements, but few of them told us much about the periodic table itself, and this is why we headed to the Illinois flatlands to see Theo Gray. Co-founder of Wolfram Research and author of the gorgeous photographic book The Elements, Theo is quite simply a world-class connoisseur of the elements, and he has the collection--2,379 elemental samples--to prove it.

Until I met Theo, the periodic table was pretty much a mystery--a series of letters and numbers that I recognized, but didn't much understand. My last encounter with the chart, like most people's, was in high school chemistry. But, as it turns out, the chart itself isn't actually that complicated--it was just that I was approaching it wrong. The trick, Theo explained, was to stop thinking like a chemist, and to start thinking...like a matchmaker. On the far right of the chart were the noble gasses, confirmed bachelors that don't mix with the riff-raff. On the far left, the alkali metals, desperate lonely hearts that react with nearly every element that comes along. In between were the metals, elements that sometimes react, and sometimes don't. And this genius chart that has persisted without challenge for more than a century is the predictive key, pinpointing which pairs will last, and which will go bust.

Is it a love connection? Image via Wikipedia .

It's not easy to make a television show about a list of elements, especially one that most people recognize but don't know how to read. Even more daunting, the periodic table doesn't just catalog the elements. It describes their atoms, and the squares around their names are arranged from left to right by the increasing number of protons inside their atoms' nuclei. That alone is more chemistry than most non-chemists want to think about.

But this is where Theo Gray comes in. To understand the chart, he explained, you don't have to know a thing about atoms. A case in point: Dmitri Mendeleev, the 19th-century Russian scientist who created the periodic table, invented it before the structure of atoms was even discovered. He knew the elements' physical characteristics and how they behaved chemically when they came into contact with each other, but he knew nothing about protons, neutrons, and electrons. This, Theo explained, is the key to decoding the periodic table--and Mendeleev's stroke of genius. Without knowing any of the physics to explain the phenomenon, Mendeleev realized it was the elements' behavior--and their reactivity to each other--that should determine the chart's organization. And there has never been a experiment in the century since he designed the chart that has proven him wrong.

To see what he was talking about, Theo told us, we'd have to step into his Lair where he'd set up a makeshift lab bench. Above it, he had hung a net of popcorn and when we tasted it (which we did), it was clear it was in need of a certain seasoning. To improve the taste, however, we'd all have to suit up in protective eyewear, and David Pogue, Theo's designated on-camera assistant, would have to be encased in a flame-retardant shirt and gloves. The experiment, Theo explained, involved two of the most reactive elements on the periodic table: chlorine gas, which can liquefy your insides, and sodium metal, which explodes on contact with water.

Making salt.

What we had were two "desperate Lonely Hearts," Theo explained--two unstable elements that would readily react with each other. Lonely Heart Number One, sodium, came from the table's far left-hand column of the alkali metals, while Lonely Heart Number Two, chlorine, lived on the other side of the table in the halogen column, just left of the noble gasses. Alone, these elements were poisons, but when Theo allowed heated chlorine gas to come into contact with a chunk of sodium metal, a cloud of sodium chloride--salt--wafted up into the bag of popcorn.

Delicious!

Where can I find butter on the periodic table?

So how does salting up popcorn explain the structure of the periodic table? The simple answer: elements with similar chemical properties live in columns, or families, on the table, and each element in the family reacts in a similar fashion. Some families are full of giving elements, others contain desperate ones looking for handouts, and some are aloof and disconnected from their neighbors, content to fly solo.

Today we have a deeper understanding of how the particles that make up atoms conspire to produce these reactions, but Mendeleev himself didn't know any of this when he designed the table.

After visiting Theo's lair, the periodic table suddenly made sense. The chart I'd thought was just a list of individual elements is actually about their reactivity--the chemistry among elements. There is a reason we use that word to describe our human attractions--some relationships make it, and others combust. If only we humans had a table of our own to tell us which ones were which.

"Hunting the Elements" premieres Wednesday, April 4 at 9 p.m. ET on most PBS stations. Please check your local listings to confirm when it will air near you.

In the not-so-distant future, genetic testing will be a routine part of medical care. Doctors will screen for genes that influence your risk of heart disease, Alzheimer's, or diabetes. They will perform genetic tests to see how--or whether--you will respond to a particular medicine. (In fact, in some cases they already do.) It's not hard to imagine a future in which whole genome sequencing--that is, having your entire genome read out, not just a particularly juicy bit--will be routine at birth.

You may have begun to ask yourself: How much do I really want to know about my genetic destiny? But the focus on personal decision-making has obscured the legal and ethical questions that we must grapple with as policymakers and as a society. As researchers working at the intersection of law and cutting-edge medicine, these are the questions we struggle with every day. Here are our top ten legal and policy challenges that we must address as a society if we are to truly reap the benefits of genetic testing:

1. Privacy/Discrimination: Many patients are concerned about the confidentiality of their genetic test results and the potential for discriminatory use. The Genetic Information Nondiscrimination Act (GINA) prohibits employers and health insurers from using genetic information to discriminate, but does not extend to life and disability insurance or to other important molecular test results that do not fall under GINA's definition of "genetic information." Surreptitious DNA testing, in which anyone can secretly collect and test your DNA from a drinking cup, straw or licked envelope, also raises privacy concerns, as many states currently have no protections against police or private parties testing others' DNA.


2. Liability: New medical technologies result in increased errors and omissions, unrealistic or unfilled expectations, and disparities in adoption and implementation--all of which are already leading to lawsuits. As genetic testing becomes the "new normal," doctors face the most liability, but drug manufacturers, genetic test developers, testing laboratories, insurers, and even pharmacists will also be vulnerable. It remains to be seen whether these liability pressures will create incentives for diligent care, or will encourage less favorable responses such as defensive medicine, whereby doctors conduct excessive tests and procedures to protect themselves against potential lawsuits rather than because they are medically warranted.


3. Data Ownership and Management: Data is the lifeblood of genetically personalized medicine. To detect correlations and patterns that can be used to individualize care, researchers will need access to the personal genetic, lifestyle, and health data of tens if not hundreds of thousands of patients. How will these data be stored, owned, and controlled? Will patients allow researchers access to their information for research purposes? How will the data be protected against accidental release or hacking?


4. Patents: Patents are intended to promote innovation, but have stirred controversy in the genomics field when applied to naturally occurring genes, molecules, or biologic patterns. Over 20 percent of human genes are already patented, but courts are currently divided on whether those patents can actually be enforced. (Editor's note: On Monday, the Supreme Court ordered an appeals court to reconsider its ruling that two genes associated with breast cancer and ovarian cancer could be patented.)


5. Physician Participation: Doctors will be the key gatekeepers to most new genetic technologies. If doctors do not use these new tools, patients will not benefit from them. There are nowhere near enough genetic specialists to handle the genomic revolution, leaving the onus on other providers to learn genetics as it relates to their fields. Yet most doctors have little or no formal training in genetics, and many are reluctant to adopt new genetic technologies.


6. New Regulatory and Reimbursement Models: Traditional regulatory and reimbursement models do not take into account the complexity and novelty of new personalized medicine approaches, resulting in delays in bringing the products to market and difficulties in receiving appropriate payment from insurance companies. We will need creative new approaches to ensure that these novel products are safe and useful while not imposing undue costs, delays, and uncertainties.


7. Patient Education: The availability of genetic profiling will force us to consider how much information we want to know about ourselves and how that information will affect decisions about lifestyles, reproductive choices, financial planning, and medical interventions. Patients will need to understand the meaning and implications of these new types of data to make informed choices. Where will this education come from?


8. Direct to Consumer (DTC) Genetic Tests: Some companies have started selling genetic testing services directly to consumers. Critics argue that these tests should be available only through a doctor, in part because some DTC tests provide misleading results. Proponents of DTC testing argue that consumers should be able to access their own genetic information without having to incur the costs or confidentiality risks of obtaining their results from a doctor.


9. Disclosure of Genetic Results: Whole genome sequencing will reveal hundreds of variants in each person, many of which will have uncertain clinical significance. Should all genetic test results be returned to patients, or only those "actionable" findings for which practical steps can be taken to reduce risk? Will there be sufficient expert personnel to explain the meaning of genetic test results to patients? Is meaningful informed consent possible? When, if ever, should genetic information be disclosed to minors? Should genetic test results also be communicated to patients' relatives who may share the same traits? If so, who has the duty--the patient or the doctor?


10. Behavioral Genetics: Genetic research is not only identifying traits that affect disease risk but also is discovering genetic variants that influence our personalities and intellectual, athletic, and artistic capabilities. How will the expansion of this sensitive new information affect education programs, workplaces, and the criminal justice system, among others? Already such behavioral variants are being presented as mitigating factors in criminal trials, demonstrating that behavioral genetics is no longer science fiction.

I had just stepped off my broom at the Quidditch World Cup after losing in the quarterfinals when I got the call: "Your grandmother isn't going to make it. You need to come home." It hit me hard, but I wasn't entirely surprised. After all, it was her third cancer. It wasn't until after my grandmother passed, when my aunt was diagnosed with uterine cancer and I discovered that my great-great-grandmother had died from stomach cancer, that a voice from my genetics class started ringing in my head: "Genomics... genetic inheritance... ethical decisions...do you really want to know?"

As genetic testing becomes more accessible, more people will not only consider testing, but also have to understand the immense responsibility and ethical decisions surrounding their results. I am currently at that genetic crossroads, and I am not sure which path to take.

My maternal family history includes two incidences of gastrointestinal (GI) cancer, one a rare form; one case of breast cancer; and one diagnosis of uterine cancer. It was the diagnosis of uterine cancer that led my aunt to consider genetic testing. When I heard my aunt was considering genetic testing, I knew her decision affected me as well. To learn more about the decisions ahead of me, I visited the Massachusetts General Hospital Cancer Center, where genetic counselors assess patients' risk and help make the process of decision-making easier by providing options, a support system and advocacy for families.

My family history suggests that I could be at risk for inheriting the BRCA and Lynch syndrome mutations. BRCA 1 and BRCA 2 are tumor suppressor genes; a person who inherits a mutated BRCA gene no longer has that safeguard against tumors. BRCA is an autosomal dominant gene, which means parents with the mutation have a 50 percent chance of passing it on to their children. In an article published by the Journal for Woman's health, Stanford researchers have estimated that women with a BRCA mutation have a 60-85 percent lifetime risk of getting breast cancer and a 40-50 percent lifetime risk of getting ovarian cancer. Women without these mutations only have a 12 percent lifetime risk of breast cancer and a 2 percent risk of ovarian cancer.

Lynch syndrome, on the other hand, is comprised of five different genes that affect the GI tract in a manner similar to the way that BRCA affects the breasts and ovaries. These genes are also autosomal dominant. A positive result for Lynch syndrome means a 60-85 percent lifetime risk of colon cancer and a 40-65 percent lifetime risk of uterine cancer as well as a heightened risk for other GI cancers. In the general population, the lifetime risk of colon cancer is five percent and the lifetime risk of uterine cancer is two percent.

Some indicators of a potential mutation of these genes are several related cancers in a family, early onset of cancer, rare cancer diagnoses and people with multiple cancers. So, it is easy to understand my concern, not only for myself, but also for my family.

As genetic counselors Devanshi Patel, Janette Lawrence and Meredith Seidel explained, the first thing I need to consider is my insurance. The Genetic Information Non-discrimination Act (GINA), which went into effect in 2010, made it unlawful for health insurance companies or employers to discriminate against a person because of genetic test results. However, this does not apply to life insurance or disability insurance. Genetic counselors may suggest that patients secure life insurance before they sign up for genetic testing. As a potential patient, I will also need to know whether my insurance company covers genetic testing and counseling. Many companies cover it for people already diagnosed with cancer, but charge (over $5,000 full price) for diagnosing the BRCA and Lynch syndrome mutations in those without a cancer diagnosis.

I will also need to consider what health care choices I might make if I test positive for one of these mutations. First, I could elect to get health screens (such as mammograms and colonoscopies) earlier and more often. Getting colonoscopies yearly could reduce the risk of getting colon cancer to almost zero because it is gives doctors a chance to spot growths before they become malignant. I could also choose to go further and have prophylactic surgery--that is, have my ovaries removed--some time before I turn 35. That drastic measure reduces the risk of ovarian cancer to four percent. However, the genetic counselors explained, that intervention cannot start for a young woman until she is 25.

I will also need to consider the implications for my family members. I am lucky that my family is very close and open with each other. Often, the genetic counselors have to help patients write letters to estranged family members to alert them that they are at a high risk of cancer. In my family, the most likely person to get tested would be my aunt, because she already had cancer. If she tested positive for BRCA or Lynch syndrome, it would mean her two children have a 50 percent chance of inheriting either mutation. Although one of her children is male and breast cancer is rare in men, his lifetime risk of breast cancer would rise a hundred-fold and he would have a 50 percent chance of passing the BRCA mutation or Lynch syndrome to his offspring. If she tested negative, neither of her children would have inherited a mutation from her.

The next person to get tested would be my mother, and her results would have the same implications for my brother and me. If she tested negative, my brother and I would not inherit a mutation from her. However, a positive result for either my mother or my aunt could also have implications for my extended family. For example, if my aunt tested positive it would mean one of her parents--my grandparents--is positive as well. My grandparents' siblings would then also have a 50 percent chance of inheriting the mutation, meaning that my cousins could have the mutation as well. Additionally, if siblings get tested together, one sibling may have the mutation and the other may not. This can open up a Pandora's box of emotions from devastation to relief and from "survivors guilt" to resentment.

Finally, I will need to consider the implications for my future family. If I test positive for a mutation, it could mean rushing into relationships or having children too early. The genetic counselors at MGH told me that some parents-to-be choose in vitro fertilization so that they can have multiple embryos screened for cancer-causing mutations. Only those that do not have the mutation are implanted, thus ending the mutation in their family line forever. However, procedures like this are highly controversial and can cost more than $20,000.

Sitting in that genetics class the fall of my sophomore year, I never would have thought that what I was learning would pertain so directly to me someday. The MGH genetic counselors ask their patients, "If you have a genetic mutation with a chance of intervention, what would you do with that information?" Would you completely alter your life? Your family's lives? Or would you use the information to empower your decision-making?" I know I have asked myself all of these questions and weighed my options, but my genomic future still isn't clear. As genetic testing becomes more accessible, it's about time we all ask ourselves: What will we do with that information?

David Pogue. Image via davidpogue.com

PBS' NOVA scienceNOW NAMES DAVID POGUE AS NEW HOST FOR SCIENCE MAGAZINE SERIES IN 2012

Renowned New York Times Tech Reporter to Join Critically Acclaimed Series in Launch of Season 6 This Fall on PBS Stations Nationwide

March 15, 2012 -- NOVA scienceNOW has named David Pogue, popular technology reporter for The New York Times, to host the critically acclaimed science magazine series, senior executive producer Paula S. Apsell announced today. Pogue has signed on to the series beginning this fall with the launch of Season 6, premiering in October 2012 at 10 pm ET/PT on PBS.

David Pogue is already a familiar face to audiences of the flagship NOVA series with recent stints hosting the highly watched four-hour miniseries on materials science, Making Stuff (PBS, 2011), viewed by 14 million people, and the upcoming two-hour special program, Hunting the Elements, premiering on NOVA on April 4, 2012.

Pogue is the third host tapped to helm the acclaimed series. Prior hosts include TV and radio news correspondent Robert Krulwich, who originated the role for the series' inaugural season in January 2005, and astrophysicist Neil deGrasse Tyson, who took the reins in October 2006 and hosted seasons two through five.

"We are thrilled for David to join the NOVA scienceNOW team as host, reporting stories from the frontiers of science and technology," said Apsell. "David's engaging personality and tireless enthusiasm, as well as his natural curiosity as a tech journalist, all add up to a passion for storytelling and an ability to bring viewers on a fast-paced ride through some of the most intriguing stories and breakthroughs of our time."

Featuring four stories in each themed episode, the new season of NOVA scienceNOW, which is produced by WGBH Boston, will again tackle an array of thought-provoking topics on people's minds, such as "How Smart Can We Get?"--in which Pogue finds out how the anatomy of his brain measures up to Albert Einstein's; "What Are Animals Thinking?"--when the tech-savvy host races against homing pigeons without the aid of his iPhone's GPS; and "Can Science Stop Crime?"--in which Pogue tries to outsmart computerized lie detectors.

Other stories will follow Pogue as he discovers how much Neanderthal DNA he's carrying, meets the inventors and engineers working to create mind-reading machines and thought-controlled video games, ventures into secret labs and kitchens to uncover the hidden truths behind the mouth-watering flavors and textures we take for granted each day, and much more.

Following the weekly NOVA broadcast on Wednesday nights, the NOVA scienceNOW series will create a block of primetime science programming for viewers this fall on Wednesday nights from 9-11 pm ET/PT on PBS.

David Pogue Brief Biography

Perhaps best known as the weekly technology columnist for The New York Times, David Pogue also writes a monthly column for Scientific American. In addition, he is an Emmy Award-winning tech correspondent for CBS News,and his trademark comic tech videos appear each week on CNBC. Pogue's Twitter followers number more than 1.4 million.

With more than three million books in print, Pogue is also one of the world's best-selling how-to authors. He has written or co-written seven books in the "For Dummies" series (including Macs, Magic, Opera and Classical Music); in 1999, he launched his own series of complete, funny computer books called the "Missing Manual" series, which now includes 120 titles.

Pogue graduated summa cum laude from Yale in 1985, with distinction in music, and he spent 10 years conducting and arranging Broadway musicals in New York. He has won an Emmy, a Loeb award for journalism and an honorary doctorate in music. He has also been profiled on "48 Hours" and "60 Minutes."

Funding for NOVA scienceNOW is provided by the National Science Foundation, the Howard Hughes Medical Institute, the Alfred P. Sloan Foundation, the George D. Smith Fund, and public television viewers.

Pressrooms pbs.org/pressroom

Eileen Campion Roslan & Campion Public Relations 212.966.4600 Eileen@rc-pr.com

Karen Laverty NOVA National Promotions 617.300.4382 Karen_laverty@wgbh.org

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Last week the world of science lost one of its giants, and a great friend to NOVA.

Standing 6 feet 5, Dr. F. Sherwood Rowland, of the University of California at Irvine, brought enormous courage to groundbreaking work in chemistry that would ultimately be recognized by the 1995 Nobel Prize.

In 1974, working with his colleague Dr. Mario Molina, Rowland discovered that chlorinated fluorocarbons, or CFCs, used in aerosol sprays and coolants, had the potential to damage the Earth's ozone layer. This thin layer of gas 30,000 feet up in the stratosphere protects life on Earth from the harmful UV radiation that can cause skin cancer.

For years, the team's findings were regarded with skepticism by the scientific community. But Rowland did not shrink from speaking out on the potentially catastrophic consequences of the theory, and he strongly advised politicians and activists to push for a ban on CFCs.

A decade later, British scientists working in Antarctica proved Rowland and Molina right. With a ground-based instrument, they showed that each spring, when the sun emerged following the long polar winter, ozone levels would plunge dangerously low for several months. NASA's satellite measurements revealed the hole to be as tall as Mt. Everest and as wide as the continental United States.

No one knew what the ozone hole portended for the global ozone layer--and CFCs were chemicals that could stay in the atmosphere for 100 years. It turned out that the recurring ozone hole would be an early warning that catalyzed a global environmental treaty.

I first met Rowland in the fall of 1986, while we were producing a NOVA program on the National Ozone Expedition to Antarctica--a scientific team with the urgent mission of solving this complex puzzle of atmospheric chemistry. I remember him saying, "We've got to make hay while the sun shines." He understood that public attention on environmental issues was easily diverted and hard to sustain.

In 1987 NOVA broadcast "The Hole in the Sky," one of the world's first documentaries on ozone depletion and global warming. The program also tracked international progress toward the landmark Montreal Protocol--a global agreement to stop the production of many ozone-depleting chemicals. As Molina would later say, "We started something that was a very important precedent: people can make decisions and solve global problems."

Making complex scientific discoveries is a great contribution. Explaining what they mean to the world's future takes strength and commitment, which Sherwood Rowland had in abundance. Today's discussions of climate change could use more voices like his.