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DNA from Neanderthals can make Covid more severe – Bangkok Post

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People infected with Covid-19 who carry a specific snippet of genetic coding bequeathed by Neanderthals are three times more likely to need mechanical ventilation.

PARIS: Covid-19 patients with a snippet of Neanderthal DNA that crossed into the human genome some 60,000 years ago run a higher risk of severe complications from the disease, researchers have reported.

People infected with the new coronavirus, for example, who carry the genetic coding bequeathed by our early human cousins are three times more likely to need mechanical ventilation, according to a study published Wednesday in Nature.

There are many reasons why some people with Covid-19 wind up in intensive care and other have only light symptoms, or none at all.

Advanced age, being a man, and pre-existing medical problems can all increase the odds of a serious outcome.

But genetic factors can also play a role, as the new findings makes clear.

“It is striking that the genetic heritage from Neanderthals has such tragic consequences during the current pandemic,” said co-author Svante Paabo, director of the department of genetics at the Max Planck Institute for Evolutionary Anthropology.

Recent research by the Covid-19 Host Genetics Initiative revealed that a genetic variant in a particular region of chromosome 3 — one of 23 chromosomes in the human genome — is associated with more severe forms of the disease.

That same region was known to harbour genetic code of Neanderthal origins, so Paabo and co-author Hugo Zeberg, also from Max Planck, decided to look for a link with Covid-19.

They found that a Neanderthal individual from southern Europe carried an almost identical genetic segment, which spans some 50,000 so-called base pairs, the primary building blocks of DNA.

Tellingly, two Neanderthals found in southern Siberia, along with a specimen from another early human species that also wandered Eurasia, the Denisovans, did not carry the telltale snippet.

Modern humans and Neanderthals could have inherited the gene fragment from a common ancestor some half-million years ago, but it is far more likely to have entered the homo sapiens gene pool through more recent interbreeding, the researchers concluded.

The potentially dangerous string of Neanderthal DNA is not evenly distributed today across the globe, the study showed.

Some 16% of Europeans carry it, and about half the population across South Asia, with the highest proportion — 63% — found in Bangladesh.

This could help explain why individuals of Bangladeshi descent living in Britain are twice as likely to die from Covid-19 as the general population, the authors speculate.

In East Asia and Africa the gene variant is virtually absent.

About two percent of DNA in non-Africans across the globe originate with Neanderthals, earlier studies have shown.

Denisovan remnants are also widespread but more sporadic, comprising less than one percent of the DNA among Asians and Native Americans, and about five percent of aboriginal Australians and the people of Papua New Guinea.

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NASA probe leaking asteroid samples due to jammed door – Al Jazeera English

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Images beamed back to ground control revealed it caught more material than scientists anticipated and was spewing excess of flaky asteroid rocks into space.

A US probe that collected a sample from an asteroid earlier this week retrieved so much material that a rock is wedged in the container door, allowing rocks to spill back out into space.

On Tuesday, the robotic arm of the probe, OSIRIS-REx, kicked up a debris cloud of rocks on Bennu, a skyscraper-sized asteroid some 320 million kilometres (200 million miles) from Earth and trapped the material in a collection device for the return to Earth.

But images of the spacecraft’s collection head beamed back to ground control revealed it had caught more material than scientists anticipated and was spewing an excess of flaky asteroid rocks into space.

The leakage had the OSIRIS-REx mission team scrambling to stow the collection device to prevent additional spillage.

“Time is of the essence,” Thomas Zurbuchen, NASA’s associate administrator for science, told reporters on Friday.

Zurbuchen said mission teams will skip their chance to measure how much material they collected as originally planned and proceed to the stow phase, a fragile process of tucking the sample collection container in a safe position within the spacecraft without jostling out more valuable material.

NASA will not know how much material it collected until the sample capsule returns in 2023.

The troubleshooting also led mission leaders to forgo any more chances of redoing a collection attempt and instead commit to begin next March the spacecraft’s return to Earth.

“Quite honestly, we could not have performed a better collection experiment,” OSIRIS-REx’s principal investigator Dante Lauretta said.

But with the door lodged open by a rock and the “concerning” images of sample spillage, “we’re almost the victim of our own success here”, he added.

The roughly $800m, minivan-sized OSIRIS-REx spacecraft, built by Lockheed Martin, launched in 2016 to grab and return the first US sample of pristine asteroid materials.

Asteroids are among the leftover debris from the solar system’s formation some 4.5 billion years ago.

A sample could hold clues to the origins of life on Earth, scientists say.

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Asteroid samples escaping from jammed NASA spacecraft – Phys.org

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In this image taken from video released by NASA, the Osiris-Rex spacecraft touches the surface of asteroid Bennu on Tuesday, Oct. 20, 2020. (NASA via AP)

A NASA spacecraft is stuffed with so much asteroid rubble from this week’s grab that it’s jammed open and precious particles are drifting away in space, scientists said Friday.

Scientists announced the news three days after the named Osiris-Rex briefly touched asteroid Bennu, NASA’s first attempt at such a mission.

The mission’s lead scientist, Dante Lauretta of the University of Arizona, said Tuesday’s operation 200 million miles away collected far more material than expected for return to Earth—in the hundreds of grams. The sample container on the end of the robot arm penetrated so deeply into the asteroid and with such force, however, that rocks got sucked in and became wedged around the rim of the lid.

Scientists estimate the sampler pressed as much as 19 inches (48 centimeters) into the rough, crumbly, black terrain.

“We’re almost a victim of our own success here,” Lauretta said at a hastily arranged news conference.

Lauretta said there is nothing can do to clear the obstructions and prevent more bits of Bennu from escaping, other than to get the samples into their as soon as possible.

So, the flight team was scrambling to put the sample container into the capsule as early as Tuesday—much sooner than originally planned—for the long trip home.

“Time is of the essence,” said Thomas Zurbuchen, chief of NASA’s science missions.

This is NASA’s first asteroid sample-return mission. Bennu was chosen because its carbon-rich material is believed to hold the preserved building blocks of our solar system. Getting pieces from this cosmic time capsule could help scientists better understand how the planets formed billions of years ago and how life originated on Earth.

Scientists were stunned—and then dismayed—on Thursday when they saw the pictures coming from Osiris-Rex following its wildly successful touch-and-go at Bennu two days earlier.

A cloud of asteroid particles could be seen swirling around the spacecraft as it backed away from Bennu. The situation appeared to stabilize, according to Lauretta, once the robot arm was locked into place. But it was impossible to know exactly how much had already been lost.

The requirement for the $800 million-plus mission was to bring back a minimum 2 ounces (60 grams).

Regardless of what’s on board, Osiris-Rex will still leave the vicinity of the asteroid in March—that’s the earliest possible departure given the relative locations of Earth and Bennu. The samples won’t make it back until 2023, seven years after the spacecraft rocketed away from Cape Canaveral.

Osiris-Rex will keep drifting away from Bennu and will not orbit it again, as it waits for its scheduled departure.

Because of the sudden turn of events, scientists won’t know how much the sample capsule holds until it’s back on Earth. They initially planned to spin the spacecraft to measure the contents, but that maneuver was canceled since it could spill even more debris.

“I think we’re going to have to wait until we get home to know precisely how much we have,” Lauretta told reporters. “As you can imagine, that’s hard. … But the good news is we see a lot of material.”

Japan, meanwhile, is awaiting its second batch of samples taken from a different asteroid, due back in December.


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NASA spacecraft sent asteroid rubble flying in sample grab


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Two flights into Abbotsford have had recent COVID-19 exposures – Maple Ridge News

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Two flights to Abbotsford have each had a recent COVID-19 exposure, according to the B.C. Centre for Disease Control (CDC).

The agency indicates on its website that the flights involved were WestJet flight 637 from Calgary to Abbotsford on Wednesday, Oct. 14 (rows nine to 15) and Swoop flight 107 from Hamilton to Abbotsford on Monday, Oct. 19 (rows 20 to 26).

The CDC advises that anyone who was on these flights should self-monitor for symptoms for 14 days.

RELATED: Vancouver airport to pilot pre-flight COVID-19 tests for select WestJet passengers

Passengers on domestic flights are not required to self-isolate, but those who have travelled outside of Canada are required to self-isolate for 14 days upon their arrival.

Passengers seated on a plane with a case of COVID-19 that was later identified are no longer directly notified of their potential exposure. Instead, anyone who has travelled is asked to monitor the CDC website.

Passengers seated in the affected rows are considered to be at higher risk of exposure due to their proximity to the case.

RELATED: WestJet to offer full refunds for flights cancelled due to COVID-19 pandemic



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