7 Body Parts Scientists Can Grow in a Petri Dish

You can’t just go out and grow yourself a new heart just yet, but neither is the technology completely out of reach. Scientists have become adept at harnessing human and animal cells to grow artificial versions of complex tissues, including entire limbs. Many of the organs and other body parts researchers are bioengineering aren’t yet ready for the big-time of the human body, but we’re closer than ever to growing replacement tissue for amputees, organ transplant candidates, and more. Here are just a few body parts that can be grown in the lab.

1. Rat limb

Recently, researchers at Massachusetts General Hospital grew an entire rat arm in a dish (above). The forelimb was created with a technique called “decellularization,” which uses living donor cells to regrow organ tissue. The bioengineered rat forelimb contained bone, cartilage, blood vessels, tendons, ligaments, and nerves, and could pave the way for entire limb transplants for amputees. The research is published in the August issue of Biomaterials. 

2. Miniature brain

In 2013, scientists from the Institute of Molecular Biotechnology in Vienna, Austria announced they had successfully created a miniature brain in the lab. Using stem cells, they grew a model of a developing brain that was about the size of an embryonic human brain at nine weeks old. The cerebral organoid didn’t look exactly like a real brain, but it had active neurons and had much the same organizational structure. 

3. Breast tissue

Breast epithelial cells in a gel that encourages mammary gland growth. Image Credit: Image by Haruko Miura; Copyright HMGU

Researchers from the Helmholtz Center for Health and Environmental Research in Germany recently grew miniature mammary glands in an effort to study the development of breast cancer. Healthy tissue taken from women undergoing breast reduction surgery was turned into a gel that allowed the cells to divide and spread much like the mammary gland would during puberty. 

4. Beating heart

Scientists from the University of Pittsburgh used human skin cells to create primitive heart cells. These cells developed into heart muscle, and once exposed to a blood supply, the miniature heart (grown on a mouse heart that had had all its cells removed) began to contract spontaneously. One day, similar tissue could be used to replace heart tissue damaged by a heart attack. Heart tissue regeneration has already proven successful in monkey transplants. 

5. Ear

Image Credit: iStock

For people missing an ear, the reconstruction process is slow and painful, involving harvesting cartilage from the patient’s ribs. However, new techniques might make it easier. Physicians at Cornell University managed to 3D print a realistic ear using living cells from cows and collagen from rat tails. Others have grown ears from cow and sheep cells in the lab using a flexible wire frame.

The ear was then transplanted onto a rat to make sure it retained its shape and flexibility, as seen in the video above.

6. Kidney

Before they were growing legs, researchers at Massachusetts General Hospital created new kidneys. Using the same decellularization process, they grew rat kidneys in a lab. Once transplanted into a rat, the kidneys were able to produce urine just like a normal organ. Scientists have also produced mini-kidneys in the lab, though those have not been transplantable yet. 

7. Tear Gland

A project spearheaded by the Tokyo University of Science bioengineered the glands that produce tears and saliva in research that could help people with chronically dry eyes and mouths. The lab-grown glands were implanted in mice in 2013. The new salivary and lacrimal glands connected to nerves and ducts and were able to successfully secrete tears and saliva. 

Brooklyn Museum, Wikimedia Commons // Public Domain
Emily Warren Roebling, the Woman Who Helped Build the Brooklyn Bridge
Brooklyn Museum, Wikimedia Commons // Public Domain
Brooklyn Museum, Wikimedia Commons // Public Domain

By all accounts, Emily Roebling had an exceptional mind. Born Emily Warren on September 23, 1843, in Cold Spring, New York, she graduated with top honors from the Georgetown Visitation Convent in Washington, D.C., where she excelled in science and algebra. But in the mid-19th century, a woman entering those fields was almost unheard of—the more acceptable path for her would have been settling into the standard life of raising children in the tiny Hudson Valley community where she was born. Thankfully for the sake of New York City's iconic skyline, Emily was anything but standard.

The Warren family had been part of the Cold Spring community for generations. Its most famous member was Emily's brother, who found a place in history books as General Gouverneur Warren, a prominent Civil War figure who also helped create some of the best maps of the land west of the Mississippi River for the Corps of Topographical Engineers.

It was while Emily was visiting her brother during the war that she met Washington Roebling. The son of John Roebling—an engineer responsible for a number of prominent suspension bridges in Niagara Falls, Cincinnati, and Pittsburgh—Washington himself was a civil engineer serving underneath Gouverneur at the time. He and Emily soon began a feverish courtship that ended with their marriage in January 1865, less than a year after they first met, and just months before the war's end.

It was only a few years later that John Roebling took on the biggest job of his career: the creation of a suspension bridge that would unite Brooklyn and Manhattan. Originally called the New York and Brooklyn Bridge, the project would eventually just be known as the Brooklyn Bridge, one of the great engineering marvels of the late 19th century.

Washington and Emily were involved in the project from the start. In 1867, John Roebling sent the young couple to Europe so Washington could study the techniques used on some of the most notable bridges in France, England, and Germany, including the Clifton Suspension Bridge in Bristol, England, and the Menai Suspension Bridge in Wales.

Most importantly, Washington was to study the caisson technique, which had originated in Europe decades earlier. These pressurized chambers were the future of bridge construction—built so that water could be kept out of them to provide a dry working environment, they gave engineers the ability to build underwater on sites that were once totally inaccessible.

Sadly, John Roebling's work on the Brooklyn Bridge would be short-lived: An injury sustained while scouting construction locations in 1869 proved fatal, leaving the project in Washington's hands. Luckily, the time spent in Europe had prepared him well.

As with any construction process, Washington knew he had to focus on the foundations—the caissons, which would become the base of the iconic Brooklyn Bridge towers. These took the form of mammoth, bottomless boxes of wood and iron that were piled with large granite blocks to sink them through the muddy ground toward bedrock. As the caissons slowly sunk to their destination, workers entered through a shaft at the top and excavated the riverbed until they hit stable ground. Each caisson was pumped full of compressed air to allow the workers to remove the mud and gravel, and when it settled into its final location, it was filled with concrete. The men who built the caissons worked around the clock in hideous conditions, with most of them earning around $2 a day.

In 1872, as construction on the bridge was well underway, tragedy again struck the Roebling family. Many of the men working in the highly pressurized caissons were becoming cripplingly ill, and even dying, due to an ailment that wasn't yet understood. It was known as "caisson disease," soon to be called "the bends," a potentially deadly reaction to changes in pressure. This was a time before the principles of decompression were fully fleshed out, and Washington's penchant for appearing deep underground with his workers—sometimes staying inside for longer than a typical shift—led him to come down with the affliction. It eventually induced cramps, hindered his eyesight, and threw off his equilibrium, leaving him in near-constant pain. Though he would live for another 50 years, he would never recover (although the extent to which the bends were to blame for all of his troubles is debated).

Portrait of Washington Roebling
Washington Roebling
Théobald Chartran, Wikimedia Commons // Public Domain

Washington stayed on the project, but during the rest of the construction he observed progress through a telescope from his bedroom window on Brooklyn's Columbia Street. To communicate orders to his assistant engineers, Emily would write down detailed notes from her husband and give them to the various departments. She was his eyes and ears at the site, while doubling as nurse and confidant.

Soon enough, there were rumblings that Emily was doing much more than simply parroting information given by her husband. She was gaining a keen understanding of the engineering of the bridge and was able to speak to Roebling's assistant engineers on their level. As historian David McCullough says in his book The Great Bridge, "In truth she had by then a thorough grasp of the engineering involved. She had a quick and retentive mind, a natural gift for mathematics, and she had been a diligent student during the long years he had been incapacitated."

McCullough stresses that Emily never took over for Washington as the bridge's chief engineer, but the rumors at the time said otherwise [PDF]. A New York Times article published in 1883 quoted a source close to the family as saying, "Since her husband's unfortunate illness, Mrs. Roebling has filled his position as chief in engineering staff."

While the news about a woman at the helm of one of the most significant construction projects in New York history must have sold newspapers, according to McCullough, it also led to whisperings about the mental condition of her husband. Washington's illness was still a mystery to most, and it led to speculation he'd given Emily a larger role in the construction only because he was losing his mind. But while people on the outside were worrying, those closest to the project knew Emily's worth was immeasurable, despite not having the formal education of her husband or father-in-law. She was even becoming an "idolized figure" among assistant engineers, McCullough writes.

Construction of the Brooklyn Bridge
Construction of the Brooklyn Bridge
George Bradford Brainerd, Wikimedia // Public Domain

Histories of the Brooklyn Bridge are filled with anecdotes highlighting the importance of Emily during this time. One of the most well-known took place when representatives of a steel mill appeared on the Roeblings' doorstep to ask Washington a question about how a part of the superstructure should be formed. Only they didn't get to see Washington; instead, Emily invited them inside and sketched out the specs herself. Her quick decision-making had, according to the Times, "cleared away difficulties that had for weeks been puzzling their brains."

But Emily's job stretched far beyond her burgeoning engineering know-how. She was heavily involved in the politics of the bridge, at one point successfully lobbying for her husband when the bridge company was to vote on his ouster due to absence. And when rumors emerged that one contractor was trying to renegotiate their contract, the company sent a letter of reassurance addressed to Emily Roebling, not Washington.

For all her work on the bridge, Emily was still a doting wife, and stayed vigilant about protecting her husband's health and privacy. She made sure that visitors were rare, including Washington's own assistant engineers, and that no interviews were conducted from the bed where he was so vulnerable.

After 14 years of construction, the Brooklyn Bridge was nearly ready for its unveiling in May 1883. A week and a half before the official opening, the engineers wanted to test the new structure with an inaugural carriage ride. Everyone agreed the first rider to cross the bridge should be Emily—and she did so with a rooster on her lap, a symbol of victory, as the workers and other onlookers removed their hats and cheered her on.

At the official unveiling ceremonies on May 24, hundreds of thousands of people rushed over to celebrate the completion of the bridge that would forever alter Manhattan and Brooklyn, two separate cities on the path to becoming one. President Chester A. Arthur was among the guests, as was the governor of New York (and future president) Grover Cleveland. There was music and fireworks so dazzling they could be seen in New Jersey. Though Emily stayed for a few of the speeches, she enjoyed much of the opening day at the home her husband had been confined to for years.

It's possible that Washington Roebling never stepped foot on the bridge that he dedicated his life to. It was the bridge that killed his father and left him in constant pain, but that also helped Emily Roebling contribute to a world of engineering otherwise inaccessible to her. Today, her contributions are far from forgotten, and, along with her husband and father-in-law, she is immortalized on a plaque on the Brooklyn-side tower, which reads:

1843 - 1903
1837 - 1926
1805 - 1869


Lucy Quintanilla
How Scientists Are Using Plant-Based DNA Barcodes to Bust Counterfeiters
Lucy Quintanilla
Lucy Quintanilla

From high-end guitars to bolts that keep the wings attached to military aircraft, manufacturers are turning toward DNA to catch counterfeit products. A look inside the technology that’s sending crooks to jail in ways Sherlock Holmes only dreamed of.


Josh Davis dreamed of touring the United States with his rock band. He never dreamed the FBI would be in the audience.

Through the mid-2000s, the Josh Davis Band played Tucson, Arizona and Sioux Falls, South Dakota; Reno, Nevada and Little Rock, Arkansas; Dallas, Texas and Cheyenne, Wyoming; Bozeman, Montana and Tallahassee, Florida. The band earned extra cash selling guitars to pawn shops, hawking brands such as Gibson, Guild, and Martin. They sold each instrument for about $400 and used the cash to pay for gas, hotels, and food.

None of the guitars were authentic.

To fetch a high price, Davis and his bandmates bought cheap, unbranded guitars and painted fake trademarks on each instrument. (Later, they'd etch fake labels with a dremel hand tool, a CNC wood router, and a laser printer.) All they needed to close each deal was a gullible store clerk.

They found dozens. According to court documents, “Davis told [his drummer] that it was the responsibility of the pawn shops to determine if the guitar was fake or not." Over three years, the Josh Davis Band duped pawn shops across 22 states, selling 165 counterfeit guitars for more than $56,000.

The FBI noticed.

In 2014, Davis was tried in federal court in the eastern district of Pennsylvania, not far from the C.F. Martin & Co. guitar factory in the town of Nazareth. Eighty percent of the fake guitars had been falsely labeled as Martins. John M. Gallagher, an Assistant United States Attorney, argued on the company’s behalf: “[I]t was very difficult for us to quantify financially what money Martin Guitars or the other guitar companies are out because of this scam, but they certainly have damage to their reputation. And that’s not fair. I mean, it’s difficult for an American manufacturer to compete in a global economy as it is.”

Gallagher had a point. The Martin Guitar Company was already busy fighting a legal battle over counterfeit products in China. The Josh Davis Band just added insult to injury.

“As we encountered increased counterfeiting not just abroad, but in the United States, we wanted to find a solution,” says Gregory Paul, Martin’s Chief Technology Officer, in an interview. “We needed a technology that’s forensic grade, recognized in judicial systems around the world as definitive proof of authenticity.”

A solution would emerge in England at a Shell gas station.


The two bandits knew it all. They knew the Loomis van would be packed with cash. They knew the driver would park the van at Preston Old Road to refill an ATM. They knew the guards handling the money would be unarmed.

On a brisk December 2008 morning in Blackburn, England, the two men—dressed in black and their faces obscured by balaclavas—hid in waiting.

As expected, the Loomis van appeared and parked near the ATM. Two unarmed security guards—including Imran Aslam, a 32 year old who'd been working the job for just two months—stepped out. When Aslam revealed a cash box containing £20,000, the bandits pounced.

“Open the door or I’ll f***ing shoot you,” one of them demanded, gripping a Brocock revolver. He gestured to the locked door of the building that was to receive the money delivery. Aslam refused.

“There’s nothing I can do,” he said. “I can’t let you in.” Aslam gently placed the cash box on the sidewalk at the men’s feet. “That’s all I’ve got. That’s all I can give you."

A Loomis van on a street.
A Loomis van like the one that was robbed in the Blackburn heist.

As one thief grabbed the box, the gunman pointed the handgun at Aslam and pulled the trigger three times. Two shots whizzed into the air. A third tore into Aslam’s right thigh.

With Aslam crumpled on the sidewalk, the crooks sprinted away and escaped on a hidden getaway motorcycle. Hours later, they jimmied open the cash box, snatched up the money, and lit the empty container on fire, leaving it to smolder in the woods.

It was not the first ATM attack in the area. Months earlier, 30 miles east in the village of Thornton, the same gang had snatched a loot of £50,000. Police were grasping at dead ends until a gas station attendant noticed that a customer had paid with bills covered in peculiar stains.

It was a dead giveaway. Every Loomis cash box contains a canister of explosive dye. If anybody improperly pries open the container, the dye bursts and the money gets drenched. Suspecting the money might be stolen, the station attendant notified the police. Swabs of the bills were soon mailed to a special forensic laboratory in Stony Brook, New York.


Stony Brook is a stone's throw east of the Gatsby-esque mansions of Long Island's Gold Coast. It's a college town strung with winding suburban lanes, harborside nature preserves, and a yacht club.

It’s also the heart of America’s “DNA corridor.”

Seventeen miles west sits Cold Spring Harbor Laboratory, where James Watson first publicly described the double helix structure of DNA. Fourteen miles east is Brookhaven National Laboratory, where scientists discovered the muon-induced neutron, Maglev technology, and point DNA mutations. Stony Brook itself is command central for a biotechnology company called Applied DNA Sciences. “This area probably has the highest density of DNA scientists in the world,” James Hayward, the company’s chairman, president, & CEO, tells Mental Floss.

Stony Brook, NY
Stony Brook, New York
John Feinberg, Flickr // CC BY 2.0

Applied DNA Sciences makes, tags, and tests DNA. The company has what Hayward calls “without a doubt, one of the world’s largest capacities to manufacture DNA.” One of their products, called SigNature DNA, can be used as a “molecular barcode” that can track products and even people. It can be found in Loomis cash boxes across the United Kingdom.

In fact, the exploding dye in each Loomis box holds a unique strain of DNA created specifically for that individual container. It is invisible and impossible to scrub clean. So when forensic scientists at Applied DNA tested the suspicious bills from the English gas station, they were able to pinpoint their exact origins—the cash box stolen from Blackburn.

By New Year's Day, five conspirators, including the ATM heist's gunman, Dean Farrell, and the group's ringleader, the ironically named Colin McCash, would be arrested. (Their victim, Aslam, would live to see them in court.) Since then, the same DNA technology has been used in more than 200 similar ATM heists. All of them have led to a conviction.

It was at the time of the Blackburn bust that the Martin Guitar Company decided to sign a contract with Applied DNA Sciences. “We were aware of the work Applied DNA was doing in the UK when we began talking to them,” Gregory Paul says. “Those cases certainly underscored the value of doing it.”

Today, just like the Loomis cash boxes, more than 750,000 Martin guitars are marked with a unique invisible DNA barcode created in Stony Brook. They're all part of an expanding effort to stop what is globally a $1.7 trillion problem—counterfeiting.


Step into the Martin guitar factory in Nazareth, Pennsylvania, and you’ll see why the company goes through such lengths to protect the identity of each of its instruments. The factory floor buzzes and clangs with the sounds of woodworkers wielding chisels, lathes, sanders, and saws. Many musicians consider Martin the gold standard of acoustic guitars because of this handiwork.

The manufacturing process is involved and time-consuming. First, the wood is air dried, roasted in a kiln, and rested in a giant acclimating room for a year. (Some cuts are so rare that they must be locked in a cage.) The wood is cut with band saws and shaped by hand with bending irons. The braces inside the instrument—which prevent the guitar from collapsing on itself—are scalloped with paring knives, files, and scrapers. When workers glue the guitar, they clamp it with clothespins.

Martin clothespins
Paul Goodman, Flickr // CC BY-NC-ND 2.0

The glossing process, which gives the instrument its sheen, is as dazzling as it is exhausting. Workers apply a stain, a vinyl seal coat, a filler coat, and a second vinyl seal coat. That’s followed by a light scuffing, three coats of lacquer, some sanding, three more coats of lacquer, more sanding, a final touch-up with a brush, a glaze of lacquer, a final sanding, a polish with a buffing robot, and then one last hand polish with a buffing bonnet made of lamb’s wool.

About 560 people work here. They take pride in their work—it can take months to manufacture a guitar. But for counterfeiters, it can take just a few hours.

Musical instruments may not the first thing that pops to mind when people imagine counterfeiting—the word conjures grifters on Canal Street hawking fake Rolexes out of trench coats—but bootlegged musical instruments are a big problem. Martin knows this firsthand. In China, where copyright is awarded on a first-come, first-served basis, a guitar-maker with no affiliation with the company once registered Martin's logo, technically earning the legal right to manufacture their own “Martin” guitars. “A Chinese national has hijacked our brand and is making, unfortunately, poorly made copies of Martin guitars with my family's name on them,” Chris Martin IV, the company’s CEO, announced.

It's not just Martin. In 2010, a raid on a Chinese factory turned up 100,000 packages of fake D’Addario guitar strings. (D’Addario estimates that nearly 70 percent of the string sets sold under its name in China are fake. In 2010, the company coughed up $750,000 to fund anti-counterfeiting activities.) Four years later, U.S. Customs and Border Protection discovered a shipment of 185 guitars coming from China that suspiciously bore “Made in USA” labels. The stash of fake Gibson, Les Paul, Paul Reed Smith, and Martin guitars could have screwed consumers out of more than $1 million.

The problem of counterfeit instruments isn't just about protecting the bank accounts of companies and their consumers. "There's an element of consumer safety, too," Gregory Paul explains. "As much as guitars get counterfeited, guitar strings are counterfeited ten times as much. And those products need to possess a certain tensile strength when tuning." A cheaply-made guitar string can be dangerous; it risks snapping and injuring the performer.

Inside the Martin Guitar Factory
Paul Goodman, Flickr // CC BY-NC-ND 2.0

None of this is new. The old fake label switcheroo has been the fraudster's go-to for centuries. The composer Tomaso Antonio Vitali was complaining about it back in 1685 after he bought a phony violin:

"[T]his violin bore the label of Nicolò Amati, a maker of great repute in his profession. Your petitioner has, however, discovered that the said violin was falsely labelled, he having found underneath the label one of Francesco Ruggieri, called 'Il Pero,' a maker of much less repute, whose violins at the utmost do not realize more than three pistoles. Your petitioner has consequently been deceived by the false label."

What's new is the technology available to counterfeiters today: While faking the label of an instrument has always been relatively easy, it's been historically difficult to counterfeit the tone unique to a particular brand or model. That's changing, and it has manufacturers concerned.

All it takes to make a convincing fake is fungi. In 2009, Dr. Francis Schwarze, of the Swiss Federal Laboratories for Materials Science and Technology, hired a luthier to make a violin from wood infected with Physisporinus vitreus and Xylaria longipes, fungi known to uniquely degrade woody cell walls. When the fungal violin was tested against two 1711 Stradivarius violins, a jury of experts was asked to identify which was which; 63 percent believed the fungus-treated instrument had been made by Stradivarius.

A less earthy technique called torrefaction—a process that involves heating wood, cooling it, heating it again, and cooling it again—delivers similar results and is popular with mainstream musical instrument manufacturers. The cycle causes volatile oils, sugars, and resins to evacuate the wood, giving a brand-new instrument a rich tone reminiscent of a decades-old guitar.

Manufacturers such as Yamaha, Collings, Taylor, and Martin have all experimented with torrefaction. And while such technologies have improved the sound of new guitars, they've also fallen into the hands of counterfeiters—making it more difficult for unwitting consumers to pinpoint fraudulent products.

A microscopic barcode made of DNA could change that.


Think of DNA not as the building blocks of life, but as Mother Nature's attempt at writing code. Instead of using the dots and dashes of Morse code or the ones and zeroes of binary, DNA uses nucleotides: adenine (A), thymine (T), guanine (G), and cytosine (C).

The arrangement of those nucleotides is what differentiates your boss from a bonobo. In the 1970s, shortly after scientists learned how to synthesize arbitrary stretches of As, Ts, Cs, and Gs, experts realized that they could also encode messages with DNA in the same way that computer programmers did with ones and zeroes. (In the late 1970s, some scientists went so far to hypothesize that the DNA of viruses might contain messages from extraterrestrials; attempts to decode viral DNA found no alien fanmail.)

In 1988, Joe Davis, an artist-in-residence of sorts at MIT, became the first person to encode a message in DNA. Davis synthesized a strand of DNA—CCCCCCAACGCGCGCGCT—that, when decrypted by a computer program, visually resembled the ancient Germanic Runic figure for the female earth. The work, called Microvenus, was inserted into E. coli and reduplicated millions of times.

(We should note that this was a run-of-the-mill experiment for Davis, who is essentially a magnetic mad scientist with a penchant for performance art. He once built an aircraft powered by frog legs and concocted ways to make silkworms spin gold; a memorial he designed for the victims of Hurricane Katrina bottles up lightning and angrily redirects it back at the clouds.)

Writing about Microvenus in Arts Journal, Davis explained that, “unless it is purposefully destroyed, it could potentially survive for a period that is considerably longer than the projected lifespan of humanity itself.”

Twenty-four years later, George Church, a geneticist at Harvard University and a friend of Davis’s, converted his book Regenesis: How Synthetic Biology Will Reinvent Nature and Ourselves—about 53,426 words, 11 jpg images, and a line of JavaScript—into DNA. Like Davis, he reduplicated the DNA until he had produced 70 billion copies (making him, in a twisted way, the most published author on earth). A DNA sequencer later reassembled his book, word for word, with hardly a typo.

These biological party tricks may foreshadow the future of data storage, a world where all of our data is stored as As, Ts, Cs, and Gs. “Think of your word document stored on your laptop," explains James Hayward, Applied DNA’s president. "It’s just a lineal series of code, each bit with only two options: a zero or a one. But in DNA, each bit has four options.” Those four options mean that DNA can hold significantly larger amounts of information in a significantly smaller space. If you encoded all the information the planet produces each year into DNA, you could hold it in the palm of your hand.

In fact, Joe Davis has tinkered with that exact concept. He plans to encode all of Wikipedia into DNA, insert it into the genome of a 4000-year-old strain of apple, and plant his own Garden of Eden, growing "Trees of Knowledge" that will literally contain the world’s wisdom. (Well, Wikipedia's version of it.)


The same principles that enable Davis and Church to insert Runic art and books into DNA allow researchers at Applied DNA Sciences to create barcodes for Martin Guitar. It's a relatively simple concept: Whereas normal barcodes identify a product with a unique pattern of numbers, these barcodes use a unique sequence of nucleotides.

To do that, scientists first isolate a strand of plant DNA. They splice it, kick out any functional genetic information, shuffle the As, Cs, Ts, and Gs into a one-of-a-kind pattern, and stitch it back together. Then they make millions of copies of that strand, which are applied to the body and strings of Martin guitars.

The finished DNA barcode is genetically inert. It usually ranges from 100 to nearly 200 base pairs, long enough to create an unfathomably complicated sequence but short enough that, were it injected into a living human cell, nothing would happen: Ingesting a DNA barcode is no more dangerous than eating an Oreo. (It may even be healthier.)

"It is important to recognize that DNA is an ordinary component of food. You probably ate nearly a gram of it yesterday, which came from the DNA inside all plant and meat cells," explains MeiLin Wan, VP, Textile Sales at Applied DNA Sciences. "But because DNA is degraded down to its building blocks (A,T,C,G) before it has any chance of being taken up into the body (as ordinary nutrition) people do not become modified with plant or animal genes when we eat them … Thus, when used as a molecular bar code, DNA is as safe as food in that regard."

And while the DNA synthesized here is physically small, the sequence encoded within is substantially longer than any other barcode on the planet. “If it were a barcode, it’d be as long as your arm,” Dr. Michael Hogan, VP of Life Sciences at Applied DNA, said in a video.

And it's used for more than just musical instruments and cash boxes. These DNA barcodes are stamped onto pills, money, even vehicles. At least 10,000 high-end German cars possess a unique DNA stamp. Sweden’s largest electricity provider coats its copper supply in DNA barcodes, a move that has helped reduce theft of copper-coated wire by 85 percent. Pharmaceutical companies print DNA barcodes onto capsules and tablets to weed out dangerous fake drugs that may have slipped into the supply chain.

The Pentagon uses it too. When Vice Admiral Edward M. Straw was asked what kept him awake at night, he said nothing of IEDs or enemy combatants; he answered, “Aircraft fasteners. Nuts and bolts that hold components onto airplanes, such as wings. Wing bolts.” That's because the U.S. military’s spare parts system is rumored to contain approximately 1 million counterfeit parts—inferior nuts, bolts, and fasteners that could become a liability on the battlefield. Today, the Air Force uses DNA barcodes to ensure that junky hardware, which could wiggle or snap during flight, never sees an aircraft.

As for Martin, when I asked Gregory Paul where and how the DNA was applied onto the company's guitars, he just chuckled. "Yes. It is applied! That's all I can get into."

To see how it worked, I would have to drive to Stony Brook.


Wandering the halls of the Long Island High Technology Incubator is like peeking into the future’s window. Inside a squat set of buildings on the eastern campus of Stony Brook University, there’s a company called ImmunoMatrix, which aims to make vaccination needles obsolete; there's Vascular Simulations, which manufactures human dummies that have functioning cardiovascular systems; and there’s Applied DNA Sciences.

I wasn’t granted access to the laboratory where DNA is synthesized—the location is apparently secret, and visitors aren’t permitted because of the contamination risk—but I was permitted inside one of Applied DNA Sciences' forensic laboratories.

Only a small number of people have the clearances to enter the forensic lab here, and, of those, even fewer have access to the keys to the evidence locker. The room is locked: white walls, workstations, and a few scientists in lab coats handling equipment with names I dared not try to pronounce.

Textile Lab
The textile lab at Applied DNA Science.
Courtesy Applied DNA Science

I had imagined a room of objects waiting to be tested, guitars and airplane bolts and wads of cash. But to my surprise, all I see are small swatches of fabric. I'm told that whenever a company like Martin is testing the authenticity of a product, they simply need to swab the instrument. “There’s no way to cheat,” says Wan. “Because if there’s one molecule of our DNA, we will find it.”

Wan gets visibly excited when she talks about stopping fraud. She explains that approximately 15 percent of the goods traded around the globe are phony. Counterfeiting costs American businesses more than $200 billion a year, and the problem touches every industry. Zippo, for example, makes 12 million lighters every year, but counterfeiters match their output. Even your kitchen cabinets are unsafe: It's estimated that 50 percent of extra virgin olive oils in America are, in fact, impure. (Blame the Mafia.)

“People say this isn’t life or death, nobody is going to die from counterfeit products,” Wan says. “But this accumulated cheating casts a culture of doubt, it makes consumers and companies wonder: Am I getting ripped off? Because if you’re going to spend $500 on a Martin guitar instead of $50 on a generic instrument, then every component of that guitar should be made by Martin. Period.”

Here forensic scientists can find out who is telling the truth.

In the lab, the methods are similar to what you’d see on CSI, minus the dramatic music. Many of the scientists here previously worked in medical examiner's offices. “Everything we do is consistent with what you’d do in a human identification laboratory,” explains Dr. Ila Lansky, Director of Forensics.

To properly identify the DNA, samples from the swab in question must be multiplied, so they're ferried to an instrument called a thermal cycler. (It's basically a molecular photocopier: The DNA is heated. Then a heat-resistant enzyme called Polymerase—first discovered in the thermal springs of Yellowstone National Park—is added. When the DNA is heated once more, the Polymerase helps double the number of DNA strands.) Repeated over and over, the machine can create millions of testable samples very quickly.

The birthplace of polymerase
The birthplace of polymerase: the hot springs of Yellowstone.
Mark Ralston, AFP/Getty Images

This freshly-copied batch of DNA is placed in a refrigerator-sized machine called a 3500 Genetic Analyzer, a fluorescence-based instrument that determines the length of the DNA and the sequence of its As, Cs, Ts, and Gs. Within 20 to 120 minutes, the results appear on a computer screen in the form of a cragged graph, with wobbly peaks and valleys.

“The DNA really can’t be found unless you know what you’re looking for,” Lansky explains. “And we’re the only ones who know what to look for.”

On the day I visited, the team wasn't analyzing guitars. Instead, they were looking at cotton samples that claimed to be 100 percent pure extra-long staple, or ELS. I'm told the cotton supply chain is messy: A puffball may grow in California, be ginned in Arkansas, be woven in India, be dyed in Egypt, and then return to multiple warehouses in the United States for distribution. Each step is an opportunity for the “100 percent cotton” to become corrupted. (With sometimes horrifying results: In 2014, Italian police seized more than a million products from a company claiming to make “100 percent cashmere.” The products contained rat fur.)

Wan stands before the computer and points to the graph. To me, it’s just squiggles. She might as well have been showing me the latest stock market results. But to her eyes, it’s a damning fingerprint: She compares the contours to the peaks and valleys expected of 100 percent pure cotton. The lines don’t match.

Turns out, it's less than 80 percent ELS cotton—evidence that somebody adulterated the sample somewhere along the supply chain.

Wan smirks and says, “And that's the reason we like to say: DNA is truth."


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