How Scientists Are Saving The Dodo’s Pink Cousin

By Nayanah Siva | August 3, 2017 2:30 pm
A genetic rescue project has restored the pink pigeon population from just 12 remaining birds to over 400 today. (Vikash Tatayah/Mauritian Wildlife Foundation)

A genetic rescue project has restored the pink pigeon population from just 12 birds to over 400 today. (Vikash Tatayah/Mauritian Wildlife Foundation)

“Voldemort outlived Harry Potter,” Christelle Ferriere tells me as we walk around the small, uninhabited island of Ile aux Aigrettes, off the east coast of Mauritius. “Whoever bands them gets to name them,” she explains. Ferriere is a bird expert with the Mauritian Wildlife Foundation (MWF) and the fantastical beasts she was referring to are pink pigeons.

Pink pigeons are native only to Mauritius. And in 1990, the population was down to 12. These unique birds faced a fate similar to their extinct cousin, the dodo — the last sighting of which was reported in 1662.

But an intensive conservation project brought the pink pigeon population up to 400 within two decades, nearing the team’s goal of 600. “But getting those last 200 has not been easy,” says Vikash Tatyah, MWF’s conservation director. And there are still challenges ahead, he says.

Unlike the mainland, which is of volcanic origin, Ile aux Aigrettes is made of coral limestone. The island was declared a nature reserve in 1965. And today, 35 pink pigeons live here. You arrive by crossing glistening green-blue waters from the mainland. Stepping onto the island is like stepping back in time. Its area covers about 67 acres, but it’s still large enough to contain ghosts of several lost Mauritian species, including the infamous dodo. Yet this island is still full of hope.

Upon arriving, we are checked to ensure no unwanted seeds or guests have hitchhiked a ride that may disrupt the conservation work on the island. Like the dodo, one main cause for the pink pigeon’s decline is predators like rats and cats that steal eggs and fledglings. And even the wrong plant growing on the island could have a detrimental impact to the closely monitored habitat.

(Credit: Stephen Cussen)

The view of the main island of Mauritius from the islet of Ile aux Aigrettes. (Credit: Stephen Cussen)

There are no paths, you just have to watch your step — look out for coral embedded within the ground, hanging roots of ficus trees, untouched white ebony trees and newly planted endemic seedlings. Exotic birds call, native fruit bats hang, indigenous ornate day geckos scamper, and giant Aldabra tortoises, with names such as ‘the ghost’ and ‘big daddy,’ roam around. Conservationists have carefully considered every plant and animal on this island. That effort has led to the restoration of the forest and reintroduction of endangered species that had completely disappeared from the island.

Controversial Conservation

Not pink in the typical sense, their pale pink bodies and brown wings can make them look grayish at a distance. Their existence was once controversial. The initial project was led by Welsh biologist and conservationist Carl Jones, who was criticized for his methods, which included moving eggs from nests. Decades later, he has been hailed for bringing nine critically endangered species back to Mauritius, including the pink pigeon. He was awarded the Indianapolis Prize of conservation last year.

“Captive breeding means they took the pigeons, had them breed in captivity and let the parents rear the squabs, or even hand reared them,” explains Ferriere, referring to the baby pigeons. “Another method was cross fostering, which is when the eggs were incubated and squabs were reared by another species, Barbary doves.”

But there’s still work ahead. Forest quality is declining, Tatayah says, which affects how much food animals have. And pink pigeons are still up against a thriving predator population, as well as diseases and weak genetics.

To tackle some of these challenges, the team helps feed the endangered birds on the island. “Pink pigeons are fed maize and wheat every week,” Ferriere says.

(Credit: Stephen Cussen)

Careful restoration of the forest has allowed the reintroduction of endangered species like the pink pigeon. (Credit: Stephen Cussen)

Eggs in One Basket

The team is slowly releasing more and more sub populations of birds across Mauritius and its islets. Bird populations typically go through cyclical changes anyway, Tatayah says. “But to overcome this, the only thing we can do is to release pink pigeons in different locations across Mauritius.” They need to spread across, you would not want to put all your eggs in one basket, he says.

As was the case with the dodo, deforestation is still a real threat.

Mauritian forests — the good quality portion, anyway — are now just two percent of what existed back when the dodo was alive in the 15th century. So, until this habitat is carefully restored, pink pigeons and other precarious species will need a helping hand from bold conservationists.

And Voldemort.

CATEGORIZED UNDER: Environment, Living World

Scorpion Venom Has A Secret Ingredient: Acid

By John Wenz | August 3, 2017 12:31 pm
An emperor scorpion. (Credit: By Vova Shevchuk/Shutterstock)

An emperor scorpion. (Credit: By Vova Shevchuk/Shutterstock)

A scorpion’s sting doesn’t just impart venom — it uses a special acid to bring the pain.

In research published Wednesday in Science Advances, a team of researchers looked into why scorpion venom packs such a punch. The venom targets several pain receptors to warn away would-be predators, and it uses acid to make the sting all the more excruciating. Read More

MORE ABOUT: animals

Treating the Brain With Ultrasound and a Ceramic ‘Window’

By Nathaniel Scharping | August 2, 2017 4:40 pm
The transparent ceramic "window." (Credit: David Baillot/UC San Diego Jacobs School of Engineering)

The transparent ceramic “window.” (Credit: David Baillot/UC San Diego Jacobs School of Engineering)

One of the biggest problems in neuroscience is very simple — access. The brain is encased in the bony cranium, and many regions are buried beneath layers of brain tissue, making any intrusion potentially dangerous. Physically probing into the brain is also extremely difficult, and because you can’t just cut it open and sew it back up afterward as you might another organ, surgeons would benefit from less invasive methods. Read More

CATEGORIZED UNDER: Health & Medicine

In a First, Scientists Edit Human Embryos In a US Lab

By Eric Betz | August 2, 2017 12:00 pm

Researchers used CRISPR to prevent an embryo from inheriting a fatal heart condition.

This image sequence shows embryos developing after scientists injected CRISPR along with sperm from a man with a potentially fatal genetic mutation. The embryo developed for several days and was found to be free from the hereditary mutation. (OHSU)

This image sequence shows embryos developing after injected CRISPR along with sperm from a man with a potentially fatal genetic mutation. The embryo developed for several days and was found to be free from the hereditary mutation. (OHSU)

Earth is now one step closer to a future with genetically modified humans.

On Wednesday, scientists working at a lab in Oregon announced they’ve successfully used the gene-editing technique CRISPR to modify viable human embryos.

Researchers in China have already edited human embryos several times using CRISPR in recent years. But this is the first such effort in the United States. And their research was far more successful at knocking out the mutant gene.

The team has shown it’s possible to remove a disease-causing gene from an embryo, preventing a child from inheriting an ailment that plagued their ancestors.

“This embryo gene correction method — if proven safe — can potentially be used to prevent transmission of genetic disease to future generations,” says study co-author Paula Amato, a researcher and OB/GYN at Oregon Health and Science University in Portland.

In this study, which was published in the journal Nature, the group prevented an embryo from inheriting a potentially fatal heart condition. But scientists say this same method could be used for knocking out genes that can cause everything from cystic fibrosis to breast cancer.

Their next step is prove the technology is safe enough to begin clinical trials. That would mean implanting the gene-edited embryo into a woman, and studying the genetically engineered child. If US regulators — the Food and Drug Administration — weren’t willing to let that happen, the scientists say they’d pursue clinical trials abroad, perhaps in the United Kingdom or elsewhere.

“We would be supportive of moving this technology to different countries because these mutations are pretty common in the human population,” says Shoukhrat Mitalipov of OHSU, who led the international team. The pioneering scientist is no stranger to controversy, having already created the first three-parent baby and the first cloned human embryonic stem cells.

An Efficient Repair

This latest breakthrough is due to a new technology called CRISPR. The gene-editing tool has made altering life’s code faster and cheaper than ever before. It hacks the very system that bacteria use to spot and cut out invading viruses. And scientists can use CRISPR to simply remove a gene, or even to replace one gene with another.

In this case, their target was a mutant gene called MYBPC3 that affects one in every 500 people.

“This genetic mutation is one of the most common causes of cardiomyopathy,” Amato says. The condition causes deadly heart attacks in otherwise healthy young people. And inheriting just one copy of the gene is enough to get the disease. It’s what scientists call a heterozygous mutation.

The study used sperm from a man with this mutant MYBPC gene and a family history of cardiomyopathy. His condition is serious enough that he takes prescription heart drugs and has a defibrillator implanted under his skin and connected to his heart.

Then they used the man’s sperm to fertilize eggs from 12 female donors — injecting CRISPR at the same time. CRISPR cut out the MYBPC gene and replaced it with a healthy gene from the mother. Once the embryos were five days old, the team stopped their growth and checked to see how well their approach had wiped out the mutant gene.

They were about 72 percent efficient in knocking out the mutation. But the scientists say they’re confident they can push that number much higher.

Finally, the researchers sequenced the embryo’s genome looking for what’s called “off target effects.” This happens when CRISPR’s genetic scissors make cuts to the genome in places the scientists weren’t aiming for. It’s a common concern when using CRISPR.

Reassuringly, they didn’t find any. But the scientists say that doesn’t necessarily mean CRISPR will be as successful once scientists try to remove other diseases. Yet their findings still give hope for stopping hereditary diseases from passing from generation to generation.

“This technology can theoretically be applied to any other heterozygous mutation,” Amato says.

Hope For Clinical Trials

That includes mutations like BRCA, a common cause of breast cancer, as well as cystic fibrosis and many more. According to the study authors, this method could potentially prevent tens of thousands of mutations that affect millions of people around the world.

Mitalipov says in this initial study they used a fairly standard CRISPR approach and watched to see how well the embryos would repair the breaks. It worked surprisingly well, however, he thinks there are additional tools they could use to get even better results.

“Then I would say we would be able to proceed to clinical trials,” Mitalipov says.

Their initial focus will likely be on the heart condition-causing gene that they’ve already found success with, but there are other genes Mitalipov says he’d like to target, too.

“We would like to explore a correction for cancer genes particularly BRCA, which is inherited the same way and a single copy can cause breast cancer,” he says.

Their research doesn’t violate any U.S. regulations, but it flirts with the ragged edge of guidelines issued earlier this year.

The study was reviewed by an internal board at OHSU, and the team says they were working within the guidelines of the recently released National Academy of Sciences guidelines. But that report suggested such gene editing should only be pursued in cases where there was no “reasonable alternative” treatment.

And in this case, there is an alternative.

Instead of fixing mutant genes, doctors can simply remove the problematic embryos and only inject the healthy ones during in-vitro fertilization.

But the researchers say that method is expensive and difficult on a mother. Using their approach, if it’s proven safe, could mean fewer painful injections and reduce costs.

The Gattaca Argument

Some worry this kind of technology could lead to “designer babies,” where parents alter their offspring’s DNA for more than just hereditary diseases. In theory, the technology could lead to parents with the financial means choosing to have kids that are smarter, taller, have fuller heads of hair, etc.

That dystopian vision played out in the sci-fi cult classic film Gattaca, where people are judged for being genetically inferior and jobs are denied to those with genetic heart conditions. That slippery slope to eugenics argument was even used by Kentucky Sen. Rand Paul — a physician — whose speech appeared to come from Wikipedia’s Gattaca entry.

“In your lifetime, much of your potential — or lack thereof — can be known simply by swabbing the inside of your cheek,” the senator told a Christian college in 2013. “Are we prepared to select out the imperfect among us?”

That sort of perception could make it tough to get regulatory approval to advance the research, particularly in the United States.

“At this point, it’s not clear how the clinical trials would proceed because it would depend on regulatory agencies, and they would have to tell us what is it that they require,” Mitalipov says. “There is still a long road ahead particularly if you want to do it in a really regulated way.”

For now, he’s not certain when — or where — they might be able to push forward.

CATEGORIZED UNDER: Health & Medicine, top posts

When Having Less Fat Isn’t Always Better

By Nathaniel Scharping | August 1, 2017 5:12 pm
(Credit: By VGstockstudio/Shutterstock)

(Credit: By VGstockstudio/Shutterstock)

If the recent debate over being “fat but fit” taught us anything it’s that our health is anything but binary. Carrying around a few extra pounds is by no means an indicator of overall health, and being slim doesn’t guarantee longevity. As scientists tease apart the components of a individual fitness, they must consider cardiovascular, metabolic, mental and immune health, as well as other factors. Even when it comes to fat, new research confirms it may be less about how much we have and more about what kinds of fat our bodies hold on to, and where they do it.

White Hat Fat   

Fat comes in two main categories: the visceral fat that surrounds our organs and the subcutaneous fat that lies just under the skin. Most of our fat is subcutaneous, and that’s a good thing, because it’s much better for our bodies. Visceral fat cells tend to let go of fatty lipids soon after they’re stored, allowing them into the bloodstream where they can cause health problems. This realization was important because it indicated not only that the two kinds of fats affect our bodies differently, but it also hinted that fat might not necessarily be all bad.

On the flip side, doctors recently learned that some 20 percent of lean Caucasians possess two or more signs of metabolic syndrome usually only associated with overweight people. These are things like high blood pressure, elevated triglyceride and glucose levels and low HDL (or “good”) cholesterol. The effects of these symptoms were worrying — a 300 percent increase in mortality, according to Norbert Stefan, a professor at the University of Tübingen in Germany specializing in metabolic diseases.

Where the Fat Falls

After conducting a review of the literature, Stefan and his coauthors released a study today in Cell Metabolism that found a paradoxical correlation. The hallmarks of metabolic syndrome seemed to appear only in individuals with less subcutaneous fat in their legs. Those with higher levels of leg fat were actually healthier. Adding to the mystery, this puzzling connection didn’t show up in overweight individuals. And, the correlation only holds for leg fat.

Stefan thinks that it has to do with how leg fat behaves. Just as subcutaneous fat is better at holding on to lipids than visceral fat, leg fat cells are better than abdominal fat cells at keeping lipids out of the bloodstream.

“Subcutaneous leg fat is like a sponge that keeps the fat trapped. And as long as the fat is being trapped, [it does less harm] to the organs,” Stefan says.

This helpful kind of fat actually contributes to our overall health by converting fat into energy stores, as opposed to allowing it to roam around the body. Stefan’s team thinks that the 20 percent of people whose bodies don’t store leg fat likely have an impaired sensitivity to insulin, which helps our bodies store fat. (This is backed up by a 2011 study which found that variations to the IRS1 gene, which codes for a protein that helps cells respond to insulin, are associated with reduced levels of fat storage as well as metabolic issues.)

The work amounts to a further narrowing of our understanding of fat. It’s more than a jiggle around the waist, or a gelatinous mass to be extracted. Fat cells play an important role in regulating metabolic processes within our bodies, and without the right kinds in the right places, we can’t really be healthy.

CATEGORIZED UNDER: Health & Medicine
MORE ABOUT: genes & health, obesity

Your Kitchen Sponge is Covered With Bacteria — Don’t Bother Cleaning It

By Nathaniel Scharping | July 31, 2017 3:34 pm
(Credit: Africa Studio/Shutterstock)

(Credit: Africa Studio/Shutterstock)

If bacteria all glowed the way some bioluminescent species do, you’d probably go blind walking into your kitchen. An abundance of organic material and damp surfaces allows microbial life to flourish around spaces where food is prepared, but one particular item shines brightest in the bacterial firmament. It’s the kitchen sponge, that workhorse of culinary clean-ups, and it is absolutely overrun with bacteria.

Kitchen sponges have been picked out as bacterial strongholds for quite a while, though that hasn’t stopped new studies from surfacing. Each fresh revelation of microbial infestation spawns a new round of horrified media coverage, as every study seems to add to the list of potentially deadly diseases lurking in our households. The latest insights come from a team of researchers in Germany who use genetic sequencing to compile the most comprehensive list of sponge bacteria to date. Read More

CATEGORIZED UNDER: Health & Medicine, Living World

FDA to Cut Nicotine In Cigarettes to ‘Non-Addictive’ Levels

By Nathaniel Scharping | July 28, 2017 4:47 pm
(Credit: Антон Воробьев/Unsplash)

(Credit: Антон Воробьев/Unsplash)

The FDA today announced plans to reduce levels of nicotine in cigarettes, a move that is aimed at lowering smoking rates in the U.S.

In a press release, FDA commissioner Scott Gottlieb said the move will cut the amount of nicotine in cigarettes to “non-addictive” levels, although he did not specify what that meant. The agency plans to issue an Advanced Notice of Proposed Rulemaking (ANPRM) and establish a period for public and commercial input. Read More

CATEGORIZED UNDER: Health & Medicine
MORE ABOUT: personal health

There Are No Digital Natives

By Nathaniel Scharping | July 27, 2017 4:15 pm
(Credit: rangizzz/Shutterstock)

(Credit: rangizzz/Shutterstock)

Oh, kids these days. When they want to know something they Google it. When they want to buy something they go to Amazon. When they want to date someone they open Tinder.

It’s almost like they’re from a different country, one where technology has bled into every aspect of life. These so-called “digital natives” are endowed with the ability to seamlessly interact with any device, app or interface, and have migrated many aspects of their lives to the Internet. This is all to the detriment of the “digital immigrants,” those born before roughly 1984, and who have been forced to adapt to unfamiliar and fast-changing technologies.

This line of thinking dates back to 2001, when educator Marc Prensky coined the term in an essay. Digital natives, he claimed, have a newfound faculty with technology, and can handle multiple streams of information because they are adept multitaskers. What’s more, according to Prensky, educators and businesses need to toss out tradition and adapt to appease this new, tech-savvy generation.

But “digital natives” don’t exist—at least according to new research—and it may be a fool’s errand to adapt traditional methods of learning or business to engage a generation steeped in technology.

Read More

CATEGORIZED UNDER: Mind & Brain, Technology

Dancing Balls Lead to a Physics Discovery

By Nathaniel Scharping | July 26, 2017 2:14 pm

giphy (9)

Toss a few droplets of water in a hot pan and they seem to come alive, skittering to and fro as if trying to escape. Try the same thing with balls of hydrogel, and they actually could break free. The spheres bounce animatedly about a hot pan, emitting a piercing, shrieking noise as they do so.

Both tricks are due to something called the Leidenfrost effect, which describes the instantaneous vaporization that occurs when water touches a hot surface. If enough steam is produced, it can be enough to levitate water droplets above a pan, allowing them to race about without evaporating. Read More

CATEGORIZED UNDER: Space & Physics, top posts
MORE ABOUT: physics

Size and Color Saturation, a Perceptual Connection?

By Nathaniel Scharping | July 25, 2017 4:14 pm

(Credit: Shutterstock)

Paint a room in light colors to make it look bigger. Wear black to look slimmer. These are well known facts about how color influences our perception—but it’s not all black and white.

New research from Boston College is showing that color saturation — how pure a color is — affects how we perceive an objects’ size. The more saturated a color is, the bigger something looks, the researchers say, with attendant implications for marketing and design. More than that, however, their findings also hint at how much more we need to learn about the ways colors influence cognition. Read More

CATEGORIZED UNDER: Mind & Brain, top posts
MORE ABOUT: psychology, Senses


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