Category Archives: DNA

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A DNA-based sunscreen that not only stops harmful ultraviolet (UV) light, but also becomes more protective the longer you expose it to UV rays? Thats the dazzling premise behind a recent study published in the journal Science Reports.

While sunscreen isnt the only form of sun protection (theres always protective clothing and floppy hats), the reality is that most of us just skip it. A 2015 study in Journal of the American Academy of Dermatology found that only 14.3 percent of men and 29.9 percent of women routinely use sunscreen when they are in outside for more than an hour. This wouldnt be a problem, except, Ultraviolet light is a carcinogen, Guy German a biomedical researcher at Binghamton University in New York and an author on the study, tells PopSci. We know it can give you a tan, but it can also cause cancer as well.

While dermatoepidemiologists (scientists who study diseases of the skin) suspect that sunlight causes cancer because it damages DNA in our cells, German and his colleagues were looking at DNA in an entirely different way. They wondered what would happen if they exposed DNA film, essentially a thin sheet of the stuff, to the same kind of ultraviolet light we get from walking in sunshine.

If youve ever taken glue and spread it on a surface and then let it dry to create a sheet or film, then you understand the basics of the material the researchers made: They took a liquid solution of DNA, smeared it on a piece of glass, and let it dry to create the film. The DNA, in case you were wondering, comes from salmon sperm. It was not that we chose salmon sperm, says German. Its just one of the readily available DNA sources.

German, along with the lead author on the study, Alexandria Gasperini, then exposed the film to UVA and UVB light to see how much, if any, radiation the films would allow to pass. UVA light makes up around 95-percent of the suns radiative light; it can penetrate deep into the skin, has long-been thought to be a culprit in premature aging, and is increasingly believed to play a key role in the formation of skin cancer. UVB, the radiation that makes us tan (and burn), also plays a role in skin cancer.

This was a fundamental study to see how UV light interacts with DNA films, says German, Also, you know subsequently how the UV light can actually alter DNA films.

To measure these effects, the team used a device called a spectrophotometer, which allows them to control the amount and wavelength of light that they put through the films. A receptor on the other side measured how much of the light passed made it through. The DNA film did not allow up to 90 percent of UVB light and 20-percent of UVA light to cross through. Perhaps even more amazing: The DNA film seemed to grow strongerthat is, it seemed to allow less light to pass through the longer it was exposed to UV light. German and his team, however, arent sure if the films achieve this by absorbing light or reflecting it.

We discovered two possible mechanisms, says German to explain how the DNA films appear to achieving this feat. One is called hyperchromicity, that is the increased ability of DNA films to absorb UV light, but also we found that the results that we got suggest a crosslinking density of the molecules themselves.

Under a microscope, the films crystalline structure got denser, or developed more crosslinks, as it was exposed to more light. The results suggest that, if a film has more crosslinks, its potentially going to absorb or scatter more UV light.

As an added bonus, the team also found that when they coated the film on human skin samples procured from elective surgeries, it also helped the skin retain moisture.

To be clear, what German and his team tested is not sunscreen, at least not in the traditional sense of a liquid or paste smeared onto the skin. You cant pick this up at the supermarket, at least not anytime soon. But between the ecological and health concerns of chemical sunscreens, and the lack of efficacy of mineral sunscreens, what they uncovered, might make its way into products in the future. Who wouldnt want a sunscreen that you apply once? That grows stronger the longer you frolic in the sun? It would, in a sense, act as a sacrificial layer, taking one for the team and allowing your own skin to go unscathed.

This article appeared originally on Popular Science.

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Sunscreen Made From DNA Would Last Forever - HuffPost

Pacific Standard

New DNA Extraction Techniques Are Helping Enhance Our Understanding of Elephants' Biological History Pacific Standard The first DNA analysis of ancient straight-tusked elephant fossils may be changing what we know about elephant evolution. Scientists have presumed that a species of giant elephant called Palaeoloxodon antiquus, which roamed across Europe and Asia over ...

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New DNA Extraction Techniques Are Helping Enhance Our Understanding of Elephants' Biological History - Pacific Standard

Jason Stockley is charged with the December 2011 premeditated shooting death of 24-year-old Anthony Lamar Smith.

Jacob Long, KSDK 6:54 PM. CDT August 03, 2017

Former SLMPD officer Jason Stockley has been charged with first-degree murder for a 2011 killing on West Florissant. (Photo: Houston PD, Custom)

ST. LOUIS - The third day of testimony has concluded in the high-profile murder trial of ex-St. Louis Police Officer Jason Stockley.

Circuit Attorney Kim Gardner said the state was on the verge of resting its case, but that there were still pending decisions and motions that need to be ruled on.

That outstanding business is expected to be addressed early next week. Once the state officially wraps its case, the defense is expected to begin calling witnesses.

So far, 18 witnesses and more than 100 exhibits have been presented to the court since the trial began this past Tuesday.

Stockley is charged with first-degree murder and armed criminal action for the December 2011 shooting death of Anthony Lamar Smith, 24.

The deadly encounter followed a suspected drug deal involving Smith and a high-speed police chase in parts of north St. Louis.

Dr. Karen Preiter, a DNA analyst with St. Louis Police, was the last state witness to testify on Thursday afternoon.

She said there was a partial DNA profile matching Stockley located on the trigger, grip and rough area of a 38mm Taurus revolver recovered from the shooting scene.

She said his DNA profile was also found on a screw in the revolver. She said no DNA profile matching Smith was found on the weapon.

Its an important piece of evidence for the states case, as prosecutors have alleged the firearm was planted by Stockley following the shooting.

The ex-cop is seen on video going back and forth between Smiths car and the duty bag located in the back of his department SUV on scene. Prosecutors have even alleged Stockley blocked a back seat internal camera with his body as he removed something from the bag.

Preiter said the chances of finding another Caucasian person with the same profile are 1/200 billion and 1/10 trillion for an African-American person.

Stockley was also the major contributor for DNA recovered on his personal AK47 that was recovered from the scene. Prosecutors said Stockley used the firearm when he first fired upon Smiths vehicle in the parking lot of a Churchs Chicken following the suspected drug deal that prompted the chase.

During cross-examination, defense attorneys alleged Stockleys DNA was on the gun because he rendered it safe by unloading it on scene.

Theyve said previously that no department policy in 2011 barred Stockley from entering or re-entering a vehicle that was involved an officer-involved shooting.

The defense has also claimed that its possible to touch something and not leave DNA. They believe the gun belonged to Smith and was one reason why Stockley was in fear of his life.

Earlier in the day, an FBI gunshot residue expert testified one of the five shots that killed Smith was fired within six inches of his body. Prosecutors have described it as a kill shot.

2017 KSDK-TV

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Alleged drop gun contained DNA of ex-St. Louis police officer - KSDK

A Mycenaean woman depicted on a fresco at Mycenae on mainland Greece.

Yann Forget/Wikimedia Commons

By Ann GibbonsAug. 2, 2017 , 1:00 PM

Ever since the days of Homer, Greeks have long idealized their Mycenaean ancestors in epic poems and classic tragedies that glorify the exploits of Odysseus, King Agamemnon, and other heroes who went in and out of favor with the Greek gods. Although these Mycenaeans were fictitious, scholars have debated whether todays Greeks descend from the actual Mycenaeans, who created a famous civilization that dominated mainland Greece and the Aegean Sea from about 1600 B.C.E. to 1200 B.C.E., or whether the ancient Mycenaeans simply vanished from the region.

Now, ancient DNA suggests that living Greeks are indeed the descendants of Mycenaeans, with only a small proportion of DNA from later migrations to Greece. And the Mycenaeans themselves were closely related to the earlier Minoans, the study reveals, another great civilization that flourished on the island of Crete from 2600 B.C.E. to 1400 B.C.E. (named for the mythical King Minos).

The Lion Gate was the main entrance to the Bronze Age citadel of Mycenae, the center of the Mycenaean civilization.

RnDmS/iStockphoto

The ancient DNA comes from the teeth of 19 people, including 10 Minoans from Crete dating to 2900 B.C.E. to 1700 BCE, four Mycenaeans from the archaeological site at Mycenae and other cemeteries on the Greek mainland dating from 1700 B.C.E. to 1200 B.C.E., and five people from other early farming or Bronze Age (5400 B.C.E. to 1340 B.C.E.) cultures in Greece and Turkey. By comparing 1.2 million letters of genetic code across these genomes to those of 334 other ancient people from around the world and 30 modern Greeks, the researchers were able to plot how the individuals were related to each other.

The ancient Mycenaeans and Minoans were most closely related to each other, and they both got three-quarters of their DNA from early farmers who lived in Greece and southwestern Anatolia, which is now part of Turkey, the team reports today in Nature. Both cultures additionally inherited DNA from people from the eastern Caucasus, near modern-day Iran, suggesting an early migration of people from the east after the early farmers settled there but before Mycenaeans split from Minoans.

The Mycenaeans did have an important difference: They had some DNA4% to 16%from northern ancestors who came from Eastern Europe or Siberia. This suggests that a second wave of people from the Eurasian steppe came to mainland Greece by way of Eastern Europe or Armenia, but didnt reach Crete, says Iosif Lazaridis, a population geneticist at Harvard University who co-led the study.

This dancing Minoan woman from a fresco at Knossos, Crete (16001450 B.C.E.), resembles the Mycenaean women (above).

Wolfgang Sauber/Wikimedia Commons

Not surprisingly, the Minoans and Mycenaeans looked alike, both carrying genes for brown hair and brown eyes. Artists in both cultures painted dark-haired, dark-eyed people on frescoes and pottery who resemble each other, although the two cultures spoke and wrote different languages. The Mycenaeans were more militaristic, with art replete with spears and images of war, whereas Minoan art showed few signs of warfare, Lazaridis says. Because the Minoans script used hieroglyphics, some archaeologists thought they were partly Egyptian, which turns out to be false.

The continuity between the Mycenaeans and living people is particularly striking given that the Aegean has been a crossroads of civilizations for thousands of years, says co-author George Stamatoyannopoulos of the University of Washington in Seattle. This suggests that the major components of the Greeks ancestry were already in place in the Bronze Age, after the migration of the earliest farmers from Anatolia set the template for the genetic makeup of Greeks and, in fact, most Europeans. The spread of farming populations was the decisive moment when the major elements of the Greek population were already provided, says archaeologist Colin Renfrew of the University of Cambridge in the United Kingdom, who was not involved in the work.

The results also show it is possible to get ancient DNA from the hot, dry landscape of the eastern Mediterranean, Renfrew says. He and others now have hope for getting DNA from groups such as the mysterious Hittites who came to ancient Anatolia sometime before 2000 B.C.E. and who may have been the source of Caucasian ancestry in Mycenaeans and early Indo-European languages in the region. Archaeologist Kristian Kristiansen of the University of Gothenburg in Sweden, who was not involved in the work, agrees. The results have now opened up the next chapter in the genetic history of western Eurasiathat of the Bronze Age Mediterranean.

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The Greeks really do have near-mythical origins, ancient DNA reveals - Science Magazine

The first sign of successful in vitro fertilization, after co-injection of a gene-correcting enzyme and sperm from a donor with a genetic mutation known to cause hypertrophic cardiomyopathy. Courtesy of OHSU hide caption

The first sign of successful in vitro fertilization, after co-injection of a gene-correcting enzyme and sperm from a donor with a genetic mutation known to cause hypertrophic cardiomyopathy.

Scientists have been tinkering with the DNA in humans and other living things for decades. But one thing has long been considered off-limits: modifying human DNA in any way that could be passed down for generations.

Now, an international team of scientists reports they have, for the first time, figured out a way to successfully edit the DNA in human embryos without introducing the harmful mutations that were a problem in previous attempts elsewhere. The work was published online Wednesday in the journal Nature.

"It's a pretty exciting piece of science," says George Daley, dean of the Harvard Medical School, who was not involved in the research. "It's a technical tour de force. It's really remarkable."

The research is ultimately aimed at helping families plagued by genetic diseases. The new experiment used a powerful new gene-editing technique to correct a genetic defect behind a heart disorder that can cause seemingly healthy young people to suddenly die from heart failure.

The experiment corrected the defect in nearly two-thirds of several dozen embryos, without causing potentially dangerous mutations elsewhere in the DNA.

None of the embryos were used to try to create a baby. But if future experiments confirm the techniques are safe and effective, the scientists say the same approach could be used to prevent a long list of inheritable diseases.

"Potentially, we're talking about thousands of genes and thousands of patients," says Paula Amato, an associate professor of obstetrics and gynecology at Oregon Health & Science University in Portland. She was a member of the scientific team from the U.S., China and South Korea.

Other diseases that might ultimately benefit from such an approach include Huntington's disease, cystic fibrosis, perhaps an inherited form of Alzheimer's disease and cases of breast and ovarian cancer caused by mutations in the BRCA genes.

Nonetheless, the work is setting off alarm bells among critics around the world.

"I think it's extraordinarily disturbing," says Marcy Darnovsky, who directs the Center for Genetics and Society, a genetics watchdog group in Berkeley, Calif. "It's a flagrant disregard of calls for a broad societal consensus in decisions about a really momentous technology that could be used good, but in this case is being used in preparation for an extraordinarily risky application."

"If irresponsible scientists are not stopped, the world may soon be presented with a fait accompli of the first [genetically modified] baby," says David King, who heads the U.K-based group Human Genetics Alert. "We call on governments and international organizations to wake up and pass an immediate global ban on creating cloned or GM babies, before it is too late."

Amato and others stress that their work is aimed at preventing terrible diseases, not creating genetically enhanced people. And they note that much more research is needed to confirm the technique is safe and effective before anyone tries to make a baby this way.

But scientists hoping to continue the work in the U.S. face many regulatory obstacles. The National Institutes of Health will not fund any research involving human embryos (the new work was funded by Oregon Health & Science University). And the Food and Drug Administration is prohibited by Congress from considering any experiments that involve genetically modified human embryos.

Nevertheless, the researchers say they're hopeful about continuing the work, perhaps in Britain. The United Kingdom has permitted genetic experiments involving human embryos forbidden in the United States.

"If other countries would be interested, we would be happy to work with their regulatory bodies," says Shoukhrat Mitalipov, director of the Oregon Health & Science University's Center for Embryonic Cell and Gene Therapy.

Shoukhrat Mitalipov, principal investigator for the embryo editing study, directs the Center for Embryonic Cell and Gene Therapy at Oregon Health & Sciences University. Courtesy of Kristyna Wentz-Graff/OHSU hide caption

Shoukhrat Mitalipov, principal investigator for the embryo editing study, directs the Center for Embryonic Cell and Gene Therapy at Oregon Health & Sciences University.

One major concern is safety to a developing embryo whether genetically modified human embryos would indeed produce healthy babies. But on a broader level, any changes made in the DNA of an embryo would be passed down for generations. That raises fears that any mistakes in the editing that inadvertently caused new diseases could become a permanent part of that family's genetic blueprint.

Darnovsky and others also worry that modifying human DNA in an embryo could give rise to "designer babies." That's when parents pick and choose the traits of their children to try to make them smarter, taller, stronger or have other traits that make them seem superior. That's not yet technically possible. But critics fear scientists are already moving in that direction.

"The scenario is that you would have fertility clinics advertising to people who wanted to engineer their future children so that they could be presented as 'enhanced' as biologically better than everyone else," Darnovsky says. "It's not a world we want to build. It's not a world we want to live in."

Unscrupulous researchers could also rush the technology into fertility clinics to try to start creating babies they can bill as genetically enhanced before the technology has even been proved safe, and before a societal consensus has been reached about what applications should be permitted.

"This is a strong statement that we can do genome editing," says Harvard's Daley. "The question that remains is: 'Should we?' We need a deeper public discourse around the ethical implications of this technology."

Darnovsky and some scientists argue that many couples who carry genetic diseases already have safer alternatives to this sort of gene editing. Couples carrying genetic diseases can go through in vitro fertilization (IVF) and have their embryos tested before being implanted in the womb.

"I will admit to experiencing a sense of puzzlement," says Fyodor Urnov, an associate director at the Altius Institute for Biomedical Sciences, a nonprofit research institute in Seattle.

"The question I have is: 'Why did you folks bother, given that there is a safe, effective, approved and ethical way to attain exactly the goal you have set out to do without any of the significant logical and ethic hurdles of having to edit a human embryo?" Urnov says.

Amato and the other scientists on the international team say their approach could offer an alternative for couples for whom those standard options won't work or are less desirable. But they agree the work should only move forward with careful regulatory oversight to prevent abuse.

"Anytime there's a new technology there's a potential for misuse. We have to acknowledge that," Amato says. "Personally I don't feel that's a reason not to pursue the research if you think there's a potential benefit that outweighs that risk. And I think if you can prevent serious disease in future generations, that makes it worthwhile to pursue this."

The advance was first reported last week in Technology Review, a magazine published by the Massachusetts Institute of Technology. But the details were withheld and the researchers did not elaborate until the scientific paper had finished being vetted by other scientists for publication in Nature.

For their experiments, the scientists obtained sperm from a donor carrying a mutation for the heart disorder cardiomyopathy. They then used that sperm to fertilize dozens of eggs obtained from healthy women.

At the same time as fertilization, the researchers injected a powerful, microscopic gene-editing tool known as CRISPR-Cas9. The new technique makes it much easier than previous approaches to make very precise changes in DNA.

Several scientists likened the approach to doing surgery on fetuses when they are in the womb. But this takes that idea much further and involves repairing damaged DNA at a molecular level in the womb.

"This is nano-surgery," says George Church, a prominent Harvard geneticist who also was not involved in the research. "You're doing it with the finest possible scalpel."

The editing tool very accurately cut into a mutated gene known as MYBPC3, which causes cardiomyopathy. To the researchers' surprise, the cut triggered the embryos to repair the defective gene on their own. This is a process that had previously been unknown, the scientists say.

"The most exciting moment was when we realized the mechanism of repair," Amato says. "It was fixing itself."

The researchers then let the embryos develop for several days so they could analyze them to see how well the experiments worked. In one part of the experiments involving 58 embryos, the approach corrected the mutation in more than 70 percent of the embryos, the researchers reported.

"The gene defect was corrected with high efficiency," Amato says.

In addition, a detailed genetic analysis of the embryos concluded that the gene editing had not caused safety problems.

"I think this is a significant advance," Church says. "This is important."

In 2015, Chinese scientists reported trying to edit the DNA of embryos for the first time, also using CRISPR-Cas9. But that experiment involved embryos that could never develop normally. And while those researchers did succeed in editing the targeted defect, it also produced unintended defects elsewhere in the embryos' DNA.

The scientists who conducted the new experiments say they think they avoided those problems by injecting CRISPR at the same time the eggs were being fertilized by sperm.

"That was key," Mitalipov says.

Alta Charo, a bioethicist at the University of Wisconsin, dismissed concerns about the work leading to designer babies.

"This is not the dawn of the era of the designer baby," says Charo, who co-chaired a committee formed by the National Academies of Sciences and the National Academy of Medicine to determine whether such experiments should be permissible. The committee concluded earlier this year that gene editing of human embryos could be allowed in rare cases when no other options are available but only to treat diseases.

"I do not think that the constant drumbeat about the fear of designer baby is warranted, Charo says. "What this is, is a possible step toward being able to edit the DNA in human embryos that's reliable and precise."

In the meantime, scientists in Britain have won approval to use CRISPR to edit the DNA in healthy human embryos to learn more about normal human development. A team in Sweden has started similar experiments.

"I think this needs to be tightly regulated," says Fredrik Lanner, a geneticist at the Karolinska Institute in Stockholm who is conducting those experiments. "This is very exciting. But it also could be a double-edged sword. So I think we really have to be extra cautious with this technology."

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Scientists Precisely Edit DNA In Human Embryos To Fix A Disease Gene - NPR

A fragment from a Minoan fresco showing a woman dancing. The fragment dates to between 1600 B.C. and 1450 B.C.

The Minoans and Mycenaeans were the first advanced, literate civilizations to appear in Europe. They left archaeologists with a wealth of material to pore over: palaces, golden jewelry, wall paintings, writing (some of it still undeciphered) and, of course, burials, in what is today Greece.

Now, new research on Bronze Age skeletons could shed light on the origins of the Minoan and Mycenaean people.

The study of ancient DNA suggests that there is genetic continuity between the predecessors of these ancient cultures and Greeks today. The Minoan and Mycenaean civilizations emerged from Aegean farming communities and gave rise to the Greeks who built the Parthenon and developed democracy. The findings, which were published online today (Aug. 2) in the journal Nature, also raise some questions about prehistoric migrations that set the stage for the Bronze Age. [7 Bizarre Ancient Cultures That History Forgot]

The Minoans and Mycenaeans have intrigued archaeologists from the early days of the discipline.

The Bronze Age civilization called the Mycenaeans used an early form of Greek called Linear B (shown inscribed on this tablet).

German businessman and archaeology pioneer Heinrich Schliemann set out in the 1870s to find the real-life remains of the heroic-era Homer described in "The Odyssey" and "The Iliad."He uncovered gold-rich tombs in the city of Mycenae, and since then, dozens more Mycenaean sites have been studied across mainland Greece and the Aegean Islands. The civilization, which lasted from about 1600 B.C. to 1100 B.C., produced the earliest written form of the Greek language. [10 Beasts & Dragons: How Reality Made Myth]

Just a few decades after Schliemann's exploits, British archaeologist Sir Arthur Evans revealed the ruins of a monumental, fresco-filled palace on the Greek island of Crete that predated the Mycenaeans. He called this culture "Minoan" after the mythical King Minos who ruled over Crete and occasionally sacrificed young Athenians to the labyrinth-dwelling half-man, half-bull Minotaur. The Minoans thrived on the island between 2700 B.C. and the mid-1400s B.C., when the Thera volcanic eruption on Santorini in the southern Aegean Sea may have triggered the cultures collapse. Minoan script and hieroglyphs remain untranslated, but the language is thought to be very different from Greek.

Because of some iconographic similarities with Egyptian art, Evans thought that the Minoans might have come from North Africa. In the century that followed, others proposed theories about how the Minoans and the Mycenaeans came about, wondering how much these cultures owed to other great civilizations in Mesopotamia and Egypt, said study leader Iosif Lazaridis, a geneticist at Harvard Medical School. "These theories have been difficult to test, but with ancient DNA, it is possible to say something about the origins of the people," Lazaridis told Live Science.

Lazaridis and his colleagues looked at ancient DNA samples from 19 sets of human remains that had been found at Bronze Age tombs and burial sites in the Aegeanregion. The researchers sequenced those ancient genomes and checked the DNA against a database of 332 other ancient genomes and thousands of genomes of present-day humans.

Genetically, the Minoans and Mycenaeans had the most in common with early Neolithic farmers from Greece and Turkey, the researchers found. The genomes of the Minoans and the Mycenaeans were also similar to those of modern Greek populations and to each other for the most part.

The study found that the Minoans and Mycenaeans got some of their DNA from populations farther east, from places like the Caucasus (the area between the Black Sea and the Caspian Sea) and Iran. However, only the Mycenaeans seemed to have some "northern" ancestry, which the authors speculate could represent the vestiges of a massive prehistoric migration of nomadic herders from the Eurasian steppe that eventually made it to mainland Greece but not Crete. Lazaridis was involved in a previous ancient-DNA study that pointed to such a migration as the potential source of Indo-European languages (a category that includes Greek).

John Bintliff, an archaeologist at Leiden University in the Netherlands who was not involved in the study, said some of the findings resonate with current ideas on the Minoans and Mycenaeans. For example, the fact that the Mycenaeans spoke Greek but the Minoans spoke a different, still untranslated tongue "has long suggested that the mainland and Crete were subjected to different streams of farming migrants," Bintliff told Live Science.

However, Bintliff cautioned against looking for big historic events in gene diffusion.

"The supposed 'nomad invasion' has been a long-researched issue in European prehistory, and was originally tied to innovations in weaponry and burial customs," Bintliff said. "After decades of investigation, however, most prehistorians in Eastern to Western Europe disagreed with any major arrival of new people Gene flow can occur presumably through individual smaller-scale migration of a peaceful kind, through commerce and the movement of artisans and other specialists."

Lazaridis said further research could potentially help scientists understand how these "eastern" and "northern" types of ancestry got in the DNA of Bronze Age Greeks, whether by trickling in slowly from neighboring regions over thousands of years, or bysudden big migrations.

Original article on Live Science.

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More than Myth: Ancient DNA Reveals Roots of 1st Greek Civilizations - Live Science

BBC News

DNA clue to origins of early Greek civilization BBC News DNA is shedding light on the people who built Greece's earliest civilizations. Researchers analysed genetic data from skeletons dating to the Bronze Age, a period marked by the emergence of writing, complex urban planning and magnificent art and ... The Greeks really do have near-mythical origins, ancient DNA revealsScience Magazine Ancient DNA analysis reveals Minoan and Mycenaean originsPhys.Org DNA Study Traces Greek AncestryArchaeology EurekAlert (press release) -International Business Times all 10 news articles »

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DNA clue to origins of early Greek civilization - BBC News

Of the many things that journalists are ignorant of, religion is at the top of the list. I like to collect examples of biblical illiteracy. The Associated Press once gave William Butler Yeats credit for writing Hebrews. The New York Times said that Easter marks the resurrection of Jesus into heaven.

The past few days have seen a flurry of articles claiming that a new archeological find disputes the scriptural account of the Canaanites. Heres USA Today, for example:

The Bible claimed that the ancient Canaanites were wiped out according to Gods orders, but a new genetic research study reveals a different story.

As it turns out, the Canaanites survived Gods order, and their DNA lives on in Lebanon, where over 90% of Lebanese derive their ancestry from Canaanites, according to a study published in the American Journal of Human Genetics.

The Independents headline for this explosive news was, Bible says Canaanites were wiped out by Israelites but scientists just found their descendants living in Lebanon.

The Telegraph was blunt: Study disproves the Bibles suggestion that the ancient Canaanites were wiped out. Science magazine went with, Ancient DNA counters biblical account of the mysterious Canaanites. And Cosmos Magazine declared, DNA vs the Bible: Israelites did not wipe out the Canaanites.

The New York Times led with the same angle:

There is a story in the Hebrew Bible that tells of Gods call for the annihilation of the Canaanites, a people who lived in what are now Jordan, Lebanon, Syria, Israel and the Palestinian territories thousands of years ago.

You shall not leave alive anything that breathes, God said in the passage. But you shall utterly destroy them.

But a genetic analysis published on Thursday has found that the ancient population survived that divine call for their extinction, and their descendants live in modern Lebanon.

The only problem being, of course, that all of these stories are wrong about what the Bible claims regarding the annihilation of the Canaanites.

Yes, there are passages in the Bible about God instructing Israel to destroy the Canaanites. The group is mentioned in Genesis and Exodus as inhabitants of the land God wants Israel to posess. Theyre notoriously wicked, according to biblical reports. There is a call for their annihilation. The book of Joshua is pretty much about this attempt by the Israelites to vanquish their enemies, the Canaanites. Interestingly, some scholars believe that the Canaanites created the Semitic alphabet, which developed into the Hebrew language.

Anyway, by the end of the very exciting book of Joshua, readers are told that the annihilation of the enemy is not complete. And its laid out in more detail in the book of Judges. Judges begins with yet more tales of conquests of the Canaanites. But as a section headline in my Bible states, there was a failure to complete the conquest. Here are verses 27 through 33:

However, Manasseh did not drive out the inhabitants of Beth Shean and its villages, or Taanach and its villages, or the inhabitants of Dor and its villages, or the inhabitants of Ibleam and its villages, or the inhabitants of Megiddo and its villages; for the Canaanites were determined to dwell in that land.

And it came to pass, when Israel was strong, that they put the Canaanites under tribute, but did not completely drive them out.

Nor did Ephraim drive out the Canaanites who dwelt in Gezer; so the Canaanites dwelt in Gezer among them.

Nor did Zebulun drive out the inhabitants of Kitron or the inhabitants of Nahalol; so the Canaanites dwelt among them, and were put under tribute.

Nor did Asher drive out the inhabitants of Acco or the inhabitants of Sidon, or of Ahlab, Achzib, Helbah, Aphik, or Rehob.

So the Asherites dwelt among the Canaanites, the inhabitants of the land; for they did not drive them out.

Nor did Naphtali drive out the inhabitants of Beth Shemesh or the inhabitants of Beth Anath; but they dwelt among the Canaanites, the inhabitants of the land. Nevertheless the inhabitants of Beth Shemesh and Beth Anath were put under tribute to them.

It could not be more clear. Over and over and over again, were told that the Canaanites survived.

And in the next chapter of Judges, God makes it explicit that he will not drive out the Canaanites:

Then the Angel of the Lord came up from Gilgal to Bochim, and said: I led you up from Egypt and brought you to the land of which I swore to your fathers; and I said, I will never break My covenant with you. And you shall make no covenant with the inhabitants of this land; you shall tear down their altars. But you have not obeyed My voice. Why have you done this? Therefore I also said, I will not drive them out before you; but they shall be thorns in your side, and their gods shall be a snare to you.

In the next chapter it says, Thus the children of Israel dwelt among the Canaanites And they took their daughters to be their wives, and gave their daughters to their sons; and they served their gods.

All of which to say DNA testing that shows Canaanites were not destroyed by Israelites would not refute Scripture but instead confirm it.

Some of the media outlets above slightly revised or outright corrected their stories. All were too willing to accept the assumptions in the original study, which made misleading claims about what scripture teaches regarding Canaanites.

The books of the Old and New Testaments are things that all journalists should be familiar with at a passing level, particularly if theyre going to write about them. Even a cursory knowledge of Gods covenant relationship with Israel would have been enough to avoid these missteps or false claims. These media outlets should hire people who are Sunday School teachers or otherwise familiar with the story of the land God gave to Israel. These errors are not surprising any more, but they should be avoided at a time of declining media credibility.

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Media Falsely Claim DNA Evidence Refutes Scripture - The Federalist

August 2, 2017 by David Salisbury Molecular model of the lesion that the bacterial toxin yatakemycin forms on DNA. Credit: Elwood Mullins / Vanderbilt

One of the most potent toxins known acts by welding the two strands of the famous double helix together in a unique fashion which foils the standard repair mechanisms cells use to protect their DNA.

A team of Vanderbilt University researchers have worked out the molecular details that explain how this bacterial toxinyatakemycin (YTM)prevents DNA replication. Their results, described in a paper published online July 24 by Nature Chemical Biology, explain YTM's extraordinary toxicity and could be used to fine-tune the compound's impressive antimicrobial and antifungal properties.

YTM is produced by some members of the Streptomyces family of soil bacteria to kill competing strains of bacteria. It belongs to a class of bacterial compounds that are currently being tested for cancer chemotherapy because their toxicity is extremely effective against tumor cells.

"In the past, we have thought about DNA repair in terms of protecting DNA against different kinds of chemical insults," said Professor of Biological Sciences Brandt Eichman. "Now, toxins like YTM are forcing us to consider their role as part of the ongoing chemical warfare that exists among bacteria, which can have important side effects on human health."

Cells have developed several basic types of DNA repair, including base excision repair (BER) and nucleotide excision repair (NER). BER generally fixes small lesions and NER removes large, bulky lesions.

A number of DNA toxins create bulky lesions that destabilize the double helix. However, some of the most toxic lesions bond to both strands of DNA, thereby preventing the cell's elaborate replication machinery from separating the DNA strands so they can be copied. Normally, this distorts the DNA's structure, which allows NER enzymes to locate the lesion and excise it.

"YTM is different," said postdoctoral fellow Elwood Mullins. "Instead of attaching to DNA with multiple strong covalent bonds, it forms a single covalent bond and a large number of weaker, polar interactions. As a result, it stabilizes the DNA instead of destabilizing it, and it does so without distorting the DNA structure so NER enzymes can't find it."

"We were shocked by how much it stabilizes DNA," Eichman added. "Normally, the DNA strands that we used in our experiments separate when they are heated to about 40 degrees [Celsius] but, with YTM added, they don't come apart until 85 degrees."

The Streptomyces bacteria that produce YTM have also evolved a special enzyme to protect their own DNA from the toxin. Surprisingly, this is a base excision repair enzymecalled a DNA glycosylasethat is normally limited to repairing small lesions, not the bulky adducts caused by YTM. Nevertheless, studies have shown that it is extremely effective.

It so happens that one of Streptomyces' competitors, Bacillus cereus, has managed to co-opt the gene that produces this particular enzyme. In Bacillus, however, the enzyme it producescalled AlkDprovides only limited protection.

In 2015, Eichman and Mullins reported that, unlike other BER enzymes, AlkD can detect and excise YTM lesions. At the time, they had no idea why it wasn't as effective as its Streptomyces counterpart. Now they do. It turns out that AlkD tightly binds the product that it forms from a YTM lesion, inhibiting the downstream steps in the BER process that are necessary to fully return the DNA to its original, undamaged state. This drastically reduces the effectiveness of the repair process as a whole.

In recent years, biologists have discovered that animals and plants host thousands of different species of commensal bacteria and this microscopic community, called the microbiome, plays a surprisingly important role in their health and well-being. Normally, these bacteria are beneficialfor example, converting indigestible foods into digestible formsbut they can also cause problems, such as the stomach bacteria Heliobacter pylori that can cause inflammation that produces ulcers.

"We know that bacteria produce compounds like YTM when they are under stress," Eichman observed. "The negative effects this has on their hosts is an unfortunate side effect. So it is very important that we learn as much as we can about how these bacterial toxins work and how bacteria defend against them."

Explore further: New class of DNA repair enzyme discovered

More information: Elwood A Mullins et al. Toxicity and repair of DNA adducts produced by the natural product yatakemycin, Nature Chemical Biology (2017). DOI: 10.1038/nchembio.2439

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Deciphering potent DNA toxin's secrets - Phys.Org

SmartNews Keeping you current The York Gospels (York Minster)

smithsonian.com July 31, 2017

In 2010, bioarchaeologist Matthew Collins of the University of Copenhagen and his colleagues realized that the parchment used in medieval manuscripts, which is made of scraped and stretched animal skins, was actually a repository of information about the history of domestic animals in Europe.

ChrisBaraniukatNew Scientistreports that Collins and histeam have since begun collecting the dry eraser waste of skinsleft when conservators gently cleaned the manuscripts. Using these scraps,they've been able to draw out the DNA and proteins of the animal that sourced the parchment as well as that of any bookworms and humansthat hadcome in contact with the page since.

At a recent symposium on bioarchaeology at Oxfords Bodleian Library, the researchers presentedan unpublished paperwhere they applied DNA techniques as well as traditional techniques to the 1,000-year-old York Gospels, an Anglo-Saxon manuscript, which is one of the few manuscripts to survive the Norman Conquest and the Protestant Reformation.

Ann Gibbons at Science reports that analysis of the parchment led to several surprises. For instance, the 167 folio pages of the York Gospels were made mainly from female calves, which is unusual since its believed they would normally be allowed to grow up and reproduce. But documents report that a cattle disease struck the region around the time the manuscript was produced, meaning there may have been many stillborn or sick calves around to provide the material.

Gibbons also reports that 20 percent of the DNA extracted from theYork Gospelswas human most of it from the bacteria that lived on the skin and noses of priests who took an oath by kissing certain pages. That and other bacteria could give some insight into the health of people in Middle Ages York.

A similar analysis of a Gospel of Luke manuscript by Collins and his colleagues revealedthe book was made from the skins of eight-and-a-half calves, ten-and-a-half sheep, and half a goat, as well as a cover from roe deer and a strap from fallow or red deer. Such mixed parchment suggests that scribes had to carefully manage their resources since their favored skin was not always available.

There are so many possibilities raised by the developing techniques thatGibbons reports researchers dont even know what questions to ask.Bookworm DNA could help determine what region a book was produced or traveled to; parchment DNA could help trace the changes in livestock types and breeds over time; its even possible to find the DNA of specific historical individuals who handled a book during their lifetime.

While scholars have long mined medieval manuscripts to learn about the development of language and writing styles from the texts and gleaninformation about daily life from the illustrations (and paw prints), this new lens into the manuscripts offers a whole new way to mine information frommanuscripts and bringlost chapters ofhistory to life.

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Jason Daley is a Madison, Wisconsin-based writer specializing in natural history, science, travel, and the environment. His work has appeared in Discover, Popular Science, Outside, Mens Journal, and other magazines.

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Medieval Manuscripts Are a DNA Smorgasbord - Smithsonian