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Health

Origins of plague could have emerged centuries before outbreaks, study suggests

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CNN
 — 

In the largest DNA analysis of its kind, scientists have found evidence to suggest that historic plague pandemics, such as the Black Death, were not caused by newly evolved strains of bacteria but ones that could have emerged up to centuries before their outbreaks.

The plague-causing bacterium Yersinia pestis is dated to have first emerged in humans about 5,000 years ago. Through animals and trade routes, Y. pestis spread globally over time on multiple occasions, according to a study published Thursday in the journal Communications Biology.

It caused the first plague pandemic in the sixth to eighth centuries and the second one in the 14th to 19th centuries. The latter pandemic is thought to have started with the medieval Black Death outbreak, which is estimated to have killed more than half of Europe’s population. The bacterium also caused the third plague pandemic between the 19th and 20th centuries.

By amassing 601 Y. pestis genome sequences, including modern and ancient strains, researchers from Canada and Australia were able to calculate the time when the bacterial strains likely emerged as a threat. They divided the different strains of the plague bacterium and analyzed each strain population individually.

The strain responsible for the Black Death, which the study says is thought to have begun in 1346, was newly estimated to have diverged from an ancestral strain between 1214 and 1315 — up to 132 years earlier.

The strain of Y. pestis associated with the first plague pandemic was previously recorded as first appearing during the Plague of Justinian, which began in 541. However, the researchers estimated that the strain was already present between 272 and 465 — up to almost 270 years before the outbreak.

“It shows that each major plague pandemic has likely emerged many decades to centuries earlier than what the historical record suggests,” study coauthor and evolutionary geneticist Hendrik Poinar, director of McMaster University’s Ancient DNA Centre in Canada, told CNN via email Thursday.

He added that the bacterium emerged, created small epidemics and then “for reasons we don’t quite understand,” such as famine or war, “it takes off.”

The study authors estimated that individually assessed bacterial strains from the third plague pandemic diverged from an ancestral strain between 1806 and 1901, with highly localized plague cases beginning to appear in southern China between 1772 and 1880 and later diverging into various strains that spread globally out of Hong Kong between 1894 and 1901.

The study also found evidence to support recent academic research suggesting that the third and second plague pandemics were not mutually exclusive events, but that the third was partly the continuation or tail end of the second. Despite the pandemics having their own diverse genetic lineages that evolved differently, the third descended directly from the 14th century strain that caused the second.

Poinar called this finding significant because “it takes into account that most of the history of this bacterium has been a Eurocentric view, so while plague supposedly disappeared from Europe in the 18th (century), it continued to rage in the Ottoman Empire and throughout the Middle East and likely North Africa.”

However, even with so many sequences of the plague bacterium, researchers were not able to determine the path of the global spread of the plague.

A lot of the genetic samples come from Europe. For example, the emergence of the bacterium in Africa has led to 90% of all modern plague cases occurring on the continent, yet there are no ancient sequences from the region, which is represented by just 1.5% of all genome samples — making it difficult to date the appearance of Y. pestis in Africa.

There is also far less surviving historical evidence from the second plague pandemic to help estimate its geographic origins compared with the third, with the earliest textual evidence of the pandemic in Europe coming from the Black Death in 1346, the study authors said. The researchers estimated that the second pandemic originated in Russia.

A study published in the journal Nature in June used DNA analysis to find the plague bacterium in three individuals who are dated to have died in 1338 in what’s now Kyrgyzstan in Central Asia. It provided evidence that the Black Death came from a strain originating in the area near Lake Issyk-Kul in Kyrgyzstan in the early 14th century.

The latest study concluded that more ancient DNA will be needed to refine current estimates on the early events of the second pandemic.

Via email, Poinar described the strain from Kyrgyzstan as “really fascinating” but said that it “still doesn’t sit at the root. So I would guess we’re still looking for something a good 20-50 years earlier.”

He and the other authors noted that the only way to estimate the evolution of the plague bacterium strains precisely “is with well dated sequences, such as those from skeletal remains at Lake Issyk-Kul.”

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Aging can be reversed in mice. Are people next?

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CNN
 — 

In Boston labs, old, blind mice have regained their eyesight, developed smarter, younger brains and built healthier muscle and kidney tissue. On the flip side, young mice have prematurely aged, with devastating results to nearly every tissue in their bodies.

The experiments show aging is a reversible process, capable of being driven “forwards and backwards at will,” said anti-aging expert David Sinclair, a professor of genetics in the Blavatnik Institute at Harvard Medical School and codirector of the Paul F. Glenn Center for Biology of Aging Research.

Our bodies hold a backup copy of our youth that can be triggered to regenerate, said Sinclair, the senior author of a new paper showcasing the work of his lab and international scientists.

The combined experiments, published for the first time Thursday in the journal Cell, challenge the scientific belief aging is the result of genetic mutations that undermine our DNA, creating a junkyard of damaged cellular tissue that can lead to deterioration, disease and death.

“It’s not junk, it’s not damage that causes us to get old,” said Sinclair, who described the work last year at Life Itself, a health and wellness event presented in partnership with CNN.

“We believe it’s a loss of information — a loss in the cell’s ability to read its original DNA so it forgets how to function — in much the same way an old computer may develop corrupted software. I call it the information theory of aging.”

Jae-Hyun Yang, a genetics research fellow in the Sinclair Lab who coauthored the paper, said he expects the findings “will transform the way we view the process of aging and the way we approach the treatment of diseases associated with aging.”

While DNA can be viewed as the body’s hardware, the epigenome is the software. Epigenes are proteins and chemicals that sit like freckles on each gene, waiting to tell the gene “what to do, where to do it, and when to do it,” according to the National Human Genome Research Institute.

The epigenome literally turns genes on and off. That process can be triggered by pollution, environmental toxins and human behaviors such as smoking, eating an inflammatory diet or suffering a chronic lack of sleep. And just like a computer, the cellular process becomes corrupted as more DNA is broken or damaged, Sinclair said.

“The cell panics, and proteins that normally would control the genes get distracted by having to go and repair the DNA,” he explained. “Then they don’t all find their way back to where they started, so over time it’s like a Ping-Pong match, where the balls end up all over the floor.”

In other words, the cellular pieces lose their way home, much like a person with Alzheimer’s.

“The astonishing finding is that there’s a backup copy of the software in the body that you can reset,” Sinclair said. “We’re showing why that software gets corrupted and how we can reboot the system by tapping into a reset switch that restores the cell’s ability to read the genome correctly again, as if it was young.”

It doesn’t matter if the body is 50 or 75, healthy or wracked with disease, Sinclair said. Once that process has been triggered, “the body will then remember how to regenerate and will be young again, even if you’re already old and have an illness. Now, what that software is, we don’t know yet. At this point, we just know that we can flip the switch.”

The hunt for the switch began when Sinclair was a graduate student, part of a team at the Massachusetts Institute of Technology that discovered the existence of genes to control aging in yeast. That gene exists in all creatures, so there should be a way to do the same in people, he surmised.

To test the theory, he began trying to fast-forward aging in mice without causing mutations or cancer.

“We started making that mouse when I was 39 years old. I’m now 53, and we’ve been studying that mouse ever since,” he said. “If the theory of information aging was wrong, then we would get either a dead mouse, a normal mouse, an aging mouse or a mouse that had cancer. We got aging.”

With the help of other scientists, Sinclair and his Harvard team have been able to age tissues in the brain, eyes, muscle, skin and kidneys of mice.

To do this, Sinclair’s team developed ICE, short for inducible changes to the epigenome. Instead of altering the coding sections of the mice’s DNA that can trigger mutations, ICE alters the way DNA is folded. The temporary, fast-healing cuts made by ICE mimic the daily damage from chemicals, sunlight and the like that contribute to aging.

ICE mice at one year looked and acted twice their age.

Now it was time to reverse the process. Sinclair Lab geneticist Yuancheng Lu created a mixture of three of four “Yamanaka factors,” human adult skin cells that have been reprogrammed to behave like embryonic or pluripotent stem cells, capable of developing into any cell in the body.

The cocktail was injected into damaged retinal ganglion cells at the back of the eyes of blind mice and switched on by feeding mice antibiotics.

“The antibiotic is just a tool. It could be any chemical really, just a way to be sure the three genes are switched on,” Sinclair told CNN previously. “Normally they are only on in very young, developing embryos and then turn off as we age.”

The mice regained most of their eyesight.

Next, the team tackled brain, muscle and kidney cells, and restored those to much younger levels, according to the study.

“One of our breakthroughs was to realize that if you use this particular set of three pluripotent stem cells, the mice don’t go back to age zero, which would cause cancer or worse,” Sinclair said. “Instead, the cells go back to between 50% and 75% of the original age, and they stop and don’t get any younger, which is lucky. How the cells know to do that, we don’t yet understand.”

Today, Sinclair’s team is trying to find a way to deliver the genetic switch evenly to each cell, thus rejuvenating the entire mouse at once.

“Delivery is a technical hurdle, but other groups seem to have done well,” Sinclair said, pointing to two unpublished studies that appear to have overcome the problem.

“One uses the same system we developed to treat very old mice, the equivalent of an 80-year-old human. And they still got the mice to live longer, which is remarkable. So they’ve kind of beaten us to the punch in that experiment,” he said.

“But that says to me the rejuvenation is not just affecting a few organs, it’s able to rejuvenate the whole mouse because they’re living longer,” he added. “The results are a gift and confirmation of what our paper is saying.”

What’s next? Billions of dollars are being poured into anti-aging, funding all sorts of methods to turn back the clock.

In his lab, Sinclair said his team has reset the cells in mice multiple times, showing that aging can be reversed more than once, and he is currently testing the genetic reset in primates. But decades could pass before any anti-aging clinical trials in humans begin, get analyzed and, if safe and successful, scaled to the mass needed for federal approval.

But just as damaging factors can disrupt the epigenome, healthy behaviors can repair it, Sinclair said.

“We know this is probably true because people who have lived a healthy lifestyle have less biological age than those who have done the opposite,” he said.

His top tips? Focus on plants for food, eat less often, get sufficient sleep, lose your breath for 10 minutes three times a week by exercising to maintain your muscle mass, don’t sweat the small stuff and have a good social group.

“The message is every day counts,” Sinclair said. “How you live your life even when you’re in your teens and 20s really matters, even decades later, because every day your clock is ticking.”

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Idaho murders: Suspect in student killings was seen multiple times wearing gloves, also placing garbage bags outside Pennsylvania home, source says

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CNN
 — 

The man accused of murdering four University of Idaho students in November had thoroughly cleaned the interior and exterior of his car and was also seen wearing surgical gloves multiple times before being apprehended, a law enforcement source tells CNN.

Bryan Kohberger, 28, is currently the sole suspect in the gruesome stabbings of students Kaylee Goncalves, 21; Madison Mogen, 21; Xana Kernodle, 20; and Ethan Chapin, 20, who were found dead inside their off-campus house in Moscow, Idaho, on November 13.

Kohberger, who was pursuing a PhD in criminal justice at Washington State University at the time of the killings, “cleaned his car, inside and outside, not missing an inch,” according to the law enforcement source.

The source, who spoke on the condition of anonymity, was briefed on observations made by investigators during four days of surveillance leading up to Kohberger’s arrest at his family’s Pennsylvania home on December 30.

As Kohberger now remains behind bars in Idaho awaiting his January 12 status hearing, new details have emerged elucidating some of the suspect’s movements in the days leading up to his arrest.

A surveillance team assigned to Kohberger was tasked with two missions, according to multiple law enforcement sources: keep eyes on Kohberger so they could arrest him as soon as a warrant was issued, and try to obtain an object that would yield a DNA sample from Kohberger, which could then be compared to DNA evidence found at the crime scene.

Kohberger was seen multiple times outside the Pennsylvania home wearing surgical gloves, according to the law enforcement source.

In one instance prior to Kohberger’s arrest, authorities observed him leaving his family home around 4 a.m. and putting trash bags in the neighbors’ garbage bins, according to the source. At that point, agents recovered garbage from the Kohberger family’s trash bins and what was observed being placed into the neighbors’ bins, the source said.

The recovered items were sent to the Idaho State Lab, per the source.

Last Friday, a Pennsylvania State Police SWAT team then moved in on the Kohberger family home, breaking down the door and windows in what is known as a “dynamic entry” – a tactic used in rare cases to arrest “high risk” suspects, the source added.

On Thursday, Kohberger had his initial court appearance in Idaho after he was booked into the Latah County jail Wednesday night following his extradition from Pennsylvania.

Kohberger is charged with four counts of first-degree murder and one count of burglary. He did not enter a plea at the hearing.

Authorities spent nearly two months investigating before they were able to name publicly a suspect, a task that grabbed national attention and rattled the victims’ loved ones as well as the community – which had not recorded a murder in years.

Still, the public’s view of the case remains mired with questions. As of late Thursday, it remains unclear what motivated the killings. It’s also unclear how the suspect entered the house after authorities said there was no sign of forced entry or why two roommates who were inside the residence at the time of the killings survived the attacks.

Here’s how investigators narrowed the search to Kohberger:

  • DNA: Trash recovered from Kohberger’s family home revealed that the “DNA profile obtained from the trash” matched a tan leather knife sheath found “laying on the bed” of one of the victims, according to a probable cause affidavit released Thursday. The DNA recovered from the trash “identified a male as not being excluded as the biological father” of the suspect whose DNA was found on the sheath. “At least 99.9998% of the male population would be expected to be excluded from the possibility of being the suspect’s biological father,” the affidavit said.
  • Phone records: Authorities found the suspect’s phone was near the victims’ Moscow, Idaho, home at least a dozen times between June 2022 to the present day, according to the affidavit. The records also reveal Kohberger’s phone was near the crime scene hours after the murders that morning between 9:12 a.m. and 9:21 a.m, the document says. The killings were not reported to authorities until just before noon.
  • A white sedan: A Hyundai Elantra was seen near the victims’ home around the time of their killings. Officers at Washington State University identified a white Elantra and later learned it was registered to Kohberger. The same car was also found at the suspect’s Pennsylvania family home when he was arrested last Friday. The suspect’s university is about a 10-minute drive from the Idaho crime scene.

One of two roommates who were not harmed in the attacks said she saw a masked man dressed in black inside the house on the morning of the killings, according to the probable cause affidavit.

Identified as D.M. in the court document, the roommate said she “heard crying” in the house that morning and also heard a man’s voice say, ‘It’s OK, I’m going to help you.’” D.M. said she then saw a “figure clad in black clothing and a mask that covered the person’s mouth and nose walking towards her,” the affidavit continued.

“D.M. described the figure as 5’ 10” or taller, male, not very muscular, but athletically built with bushy eyebrows,” the affidavit says. “The male walked past D.M. as she stood in a ‘frozen shock phase.’

“The male walked towards the back sliding glass door. D.M. locked herself in her room after seeing the male,” the document says, adding the roommate did not recognize the male.

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University of Idaho investigation: Police must protect information ‘at all costs,’ experts say

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CNN
 — 

The investigation into the murders of four University of Idaho students is entering a critical stage in its third week, as police are starting to receive forensic testing results from the crime scene, law enforcement experts tell CNN.

Dozens of local, state and federal investigators have yet to identify a suspect or find the murder weapon used in the attack last month in Moscow.

The public, as well as the victims’ family members, have criticized police for releasing little information, in what at times has been a confusing narrative.

But the complex nature of a high-level homicide investigation involves utmost discretion from police, experts say, because any premature hint to the public about a suspect or the various leads police are following can cause it to fall apart.

“What police have been reluctant to do in this case is to say they have a suspect, even though they have had suspects who have risen and fallen in various levels of importance, because that’s the nature of the beast,” said John Miller, CNN chief law enforcement analyst and former deputy commissioner of intelligence and counterterrorism for the New York Police Department.

“Police having no suspects is factually incorrect,” Miller said. “Police have had a number of suspects they’ve looked at, but they have no suspect they’re willing to name. You don’t name them unless you have a purpose for that. That’s not unusual.”

The victims – Ethan Chapin, 20; Kaylee Goncalves, 21; Xana Kernodle, 20; and Madison Mogen, 21 – were found stabbed on the second and third floors of their shared off-campus home on November 13, according to authorities.

The quadruple murder has upended the town of 26,000 residents, which had not recorded a single murder since 2015, and challenged a police department which has not benefited from the experience of investigating many homicides, let alone under the pressure of a national audience, Miller says.

The Moscow Police Department is leading the investigation with assistance from the Idaho State Police, the Latah County Sheriff’s Office and the FBI, which has assigned more than 40 agents to the case across the United States.

“They have really coordinated this into over 100 people that are operating as one team,” Miller said of the homicide investigation.

The FBI plays three important roles in the Idaho investigation, according to Miller.

The first involves its behavioral science unit, which is highly valuable for cases with an unknown offender because it narrows the scope of offender characteristics.

The second is its advanced technology, such as its Combined DNA Indexing System, which allows law enforcement officials and crime labs to share and search through thousands of DNA profiles.

Lastly, the FBI has 56 field offices in major cities throughout the country, which can expand the reach and capability of the investigation.

“The FBI brings a lot to this, as well as experience in a range of cases that would be beyond what a small town typically would have,” Miller said.

Every homicide investigation begins with the scene of the crime, which allows investigators only one chance to record and collect forensic evidence for processing, which includes toxicology reports on the victims, hair, fibers, blood and DNA, law enforcement experts say.

“That one chance with the crime scene is where a lot of opportunities can be made or lost,” Miller said.

Extensive evidence has been collected over the course of the investigation, including 113 pieces of physical evidence, about 4,000 photos of the crime scene and several 3D scans of the home, Moscow police said Thursday.

“To protect the investigation’s integrity, specific results will not be released,” police said.

Latah County Coroner Cathy Mabbutt told CNN she saw “lots of blood on the wall” when she arrived at the scene and police said “some” of the victims had defensive wounds.

Chances are “pretty high” a suspect could have cut themselves during the attack, so police are looking carefully at blood evidence, says Joe Giacalone, adjunct professor at John Jay College of Criminal Justice and retired NYPD sergeant who directed the agency’s Homicide School and Cold Case Squad.

Lab results from the scene can be returned to investigators fairly quickly, but in this case investigators are dealing with mixtures of DNA, which can take longer, he says.

“When you have several donors with the DNA, then it becomes a problem trying to separate those two or three or four. That could be part of the issue … toxicology reports can sometimes take a couple of weeks to come back,” Giacalone added.

The next stage in a homicide investigation is looking at the behavioral aspects of the crime. Two agents with the FBI’s Behavior Analysis Unit were assigned to the case to assess the scene and go over evidence to learn about the suspect or suspects’ behavior, based on the way they carried out the crime, Miller says.

“Understanding the victimology in a mystery can be very important, because it can lead you to motivation, it can lead you to enemies and it can lead you to friends,” he said.

Investigators will learn every detail about the four victims, their relationships with each other and the various people in their lives, Miller says. This includes cell phone records and internet records, he says, as well as video surveillance from every camera surrounding the crime scene.

“When you do an extensive video canvass, you may get a picture of a person, a shadowy figure, and then if you have a sense of direction, you can string your way down all the other cameras in that direction to see if that image reappears,” Miller said.

At this stage, investigators rely on the FBI’s Violent Criminal Apprehension Program, which collects and analyzes information about violent crimes in the United States.

The program can match a suspect’s DNA found at the scene with that of a person who is already in the system. It also scans all crimes across the country to determine if the way the attack was carried out mirrors a previous one, pointing to the same perpetrator, Miller says.

“You always start with people who are close to the victims, whether it’s love, money or drugs,” Giacalone told CNN. “That’s generally the first step that you take because most of us are victimized by someone we know. We have to ask things like, who would benefit from having this person or in this case, a group, killed?”

In an effort to locate the weapon – believed to be a fixed-blade knife – detectives contacted local businesses to see if a similar knife had been purchased recently.

“It’s highly unlikely, although not impossible, that a first-time offender is going to come prepared with a tactical knife and murder multiple people, even in the face of resistance, and that this is going to be their first encounter with violent crime or the use of a knife,” Miller said.

One aspect of a homicide investigation is to “keep the media happy,” according to Giacalone.

“Today in the social media, true crime, community-driven world in these cases, the demand for information is so great that sometimes police departments kind of fill in that blank air and say something just for the sake of saying something, and then realizing that it’s either not 100% true, or it’s misleading,” he said.

It’s critical for police to protect their information at “all costs” and they always know more than what they release to the public. Otherwise, it could cause the suspect to go on the run, he says.

Miller said it’s “not fair” to investigators for the public or media to criticize them for not releasing enough information about the case.

But, ultimately, the department has a moral obligation to share some information with families who are suffering in uncertainty, Miller says, but they must be judicious about what they share.

“If you tell them we have a suspect and we’re close to an arrest but that doesn’t come together, then everybody is disappointed or thinks you messed it up or worse, goes out and figures out who the suspect is and tries to take action on their own,” he said.

Investigators rely on the trove of physical and scientific evidence, information from the public and national data on violent crimes to cultivate possible leads, Miller says.

Public tips, photos and videos of the night the students died, including more than 260 digital media submissions people have submitted through an FBI form, are being analyzed, police say. Authorities have processed more than 1,000 tips and conducted at least 150 interviews to advance the case.

“Any one of those tips can be the missing link,” Miller said. “It can either be the connective tissue to a lead you already had but were missing a piece, or it can become the brand new lead that solves the case.”

Every tip must be recorded in a searchable database so investigators can go back to them as they learn new details over the course of the investigation, Miller says. While 95% to 99% of public tips may provide no value, one or several might crack the entire case, he adds.

“Police in this case could be nowhere tonight, having washed out another suspect, and tomorrow morning they could be making an arrest,” Miller said of the Idaho investigation. “Or, for the suspect they’re working on today, it might take them another month from now to put together enough evidence to have probable cause. That’s just something they won’t be able to reveal until it happens.”

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DNA match reunites missing daughter with her family after 51 years, family says

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CNN
 — 

A family in Fort Worth, Texas, has been reunited with their daughter who was kidnapped as a baby more than five decades ago thanks to a DNA match from the ancestry service 23andMe, the family announced Sunday.

Melissa Highsmith was just 22-months old in 1971 when she was allegedly abducted by a woman who was hired to babysit her, according to posts by the family over the years.

Highsmith – raised with the name Melanie – has lived in Fort Worth for much of her life, never knowing she was missing, according to CNN affiliate KTVT.

She had no idea her family was searching for her until they reached out to her through Facebook, she told the affiliate. At first, she thought the message may be a scam.

“My father texted me on messenger and he told me, ‘You know, I’ve been looking for my daughter for 51 years,’” Highsmith told KTVT.

The family found Highsmith through a DNA match with one her children on 23andMe, KTVT reported.

“The person that raised me, I asked her, ‘Is there anything you need to tell me?’ and it was confirmed that she knew that I was baby Melissa, so that just made it real,” Highsmith told the affiliate.

Highsmith’s parents reunited with her for the first time Saturday and did further “official and legal DNA testing,” the family wrote online.

“Although in the moment we saw her pictures, found out about her birthmark, and realized her ‘birthday’ is so close to our Melissa, WE KNEW beyond a shadow of a doubt that this was OUR GIRL,” the family added in a Facebook post announcing the news.

A profile of Highsmith’s case by the National Missing and Unidentified Persons System notes that the missing baby had a birthmark on her upper back. The report also includes a sketch of the alleged babysitter and age progression photos of Melissa.

“I just couldn’t believe it,” her mother, Alta Apantenco, told KTVT through tears, recalling the reunion. “I thought I would never see her again.”

“Our finding Melissa was purely because of DNA, not because of any police / FBI involvement, podcast involvement, or even our family’s own private investigations or speculations,” one of the Highsmith family members wrote on Facebook.

The Fort Worth Police Department was “overjoyed” that 23andMe led the family to Melissa, it said Monday in a statement, adding it would conduct official DNA testing to confirm Melissa’s identity.

The criminal statute of limitations expired 20 years after Melissa’s 18th birthday, but the department said it would continue the investigation to “uncover all of the available information concerning Melissa’s abduction that occurred 51 years ago.”

At the time of Highsmith’s disappearance, her mother said she put an ad in the paper looking for a babysitter to care for her baby while she worked, the Fort Worth Star-Telegram reported.

Apantenco said a woman responded to the ad, offering to watch Melissa at her home, the newspaper reported. When the woman arrived to pick up the baby, she said, Apantenco’s roommate was looking after the child. The roommate handed the baby to the woman, she told the paper, and the woman never returned.

The incident has always haunted Apantenco, who went on to have four more children, according to the Highsmith family.

“My mom did the best she could with the limited resources she had. She couldn’t risk getting fired. So, she trusted the person who said they’d care for her child,” Sharon Highsmith, Melissa’s younger sister, said in a news release. “For 50 years, my mom has lived with the guilt of losing Melissa. She’s also lived with community and nationwide accusations that she hurt or killed her own baby. I’m so glad we have Melissa back. I’m also grateful we have vindication for my mom.”

The family says they want others who are missing loved ones to keep believing.

“Never give up hope,” Sharon said. “Chase every lead.”

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The Black Death is still affecting the human immune system today

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CNN
 — 

The Black Death, the world’s most devastating plague outbreak, killed half of medieval Europe’s population in the space of seven years in the 14th century, shifting the course of human history.

But what about the survivors of what remains the single greatest mortality event ever recorded? New research published Wednesday in the journal Nature suggests it was more than luck that determined who lived and who died.

Analysis of centuries-old DNA from both victims and survivors of the Black Death has identified key genetic differences that helped people survive the plague, according to a study published in the journal Nature.

These genetic differences continue to shape human immune systems today, with genes that once conferred protection against the plague now linked to a greater vulnerability to autoimmune diseases such as Crohn’s and rheumatoid arthritis, the study said.

“We are the descendants of those that survived past pandemics … and understanding the evolutionary mechanisms that contributed to our survival is not only important from a scientific viewpoint, but can also inform on the mechanisms and genetic determinants of present-day susceptibility to disease,” said study coauthor Luis Barreiro, a professor of genetic medicine at University of Chicago, via email.

The seven-year study involved the extraction of DNA isolated from three different groups of skeletal remains unearthed in London and Denmark: Plague victims, those who died before the Black Death and those who died between 10 and 100 years after the plague struck.

More than 300 samples came from London, a city hit particularly hard by the plague, including from individuals buried in the East Smithfield plague pits used for mass burials at the height of the outbreak in 1348-1349. Another 198 samples were taken from human remains buried in five locations in Denmark.

DNA was extracted from dentine in the roots of individuals’ teeth, and researchers were also able to check for the presence of Yersinia pestis, the bacterium that causes plague. They then searched for signs of genetic adaption to the disease.

“It’s a LONG process, but in the end you have the sequence of those genes for those people from before, during and after the plague and you can ask: Do the genes one population carried looked different than the ones another population carried,” said coauthor Hendrik Poinar, a professor of anthropology at McMaster University in Hamilton, Ontario in an email.

The team pinpointed a variant of one particular gene, known as ERAP 2, that appeared to have a strong association with the plague. Before the Black Death, the variant of ERAP2 found to be protective of the plague was found in 40% of individuals included in the London study. After the Black Death, it was 50%. In Denmark, the percentile disparity was starker — it changed from about 45% of samples buried before the plague to 70% buried afterwards.

The team don’t yet know exactly why this variant conferred protection, but their lab experiments in cultured cells indicated that, in people with the ERAP 2 variant, an immune cell known as a macrophage provoked a very different response to Yersinia pestis, Barreiro explained. Macrophages from individuals with the variant were better able to kill the bacteria in lab experiments than from macrophages from individuals lacking it.

“We do not know if it still protects against the plague given that the number of cases in present day populations is very low but we speculated that it should,” he said. It’s also likely that the variant is beneficial against other pathogens — although this wasn’t part of the research.

The downside to the variant is that it has been linked to a greater susceptibility to autoimmune disorders, such as Crohn’s disease, where the immune system becomes overactive.

“This suggests that populations that survived the Black Death paid a price, which is to have an immune system that increases our susceptibility to react against ourselves,” Barreiro said.

He said that it was unlikely that Covid-19 outbreak would shape our immune system in a similar way — largely because the disease predominantly kills people after their reproductive age, meaning it’s unlikely genes that confer protection would be passed on to the next generation.

This change in human genetic makeup occurring in a matter of decades is also a rare example of rapid natural selection, said David Enard, a professor in the University of Arizona’s department of ecology and evolutionary biology, who was not involved in the research.

“The narrow time window from which samples were taken, and the large number of samples analysed, are selling points of the study, he said in a commentary published alongside the study, “allowing the authors to accurately date natural selection.”

“Even though evolutionary biologists had previously wondered about the possibility of natural selection during the Black Death, proper investigation was not possible without this precise dating of many samples.”

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Rodney Reed: Supreme Court hears death row inmate’s appeal for new DNA testing

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CNN
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The Supreme Court struggled with the case of Rodney Reed on Tuesday, a Black death row inmate seeking post-conviction DNA evidence to prove his innocence. He claims an all-White jury wrongly convicted him of killing a White woman in Texas in 1998.

Since his conviction, Texas courts have rejected his various appeals. Celebrities such as Kim Kardashian and Rihanna have expressed support, signing a petition asking the state to halt his execution.

At oral arguments, a lawyer for the state suggested Reed was making his arguments in order to delay his execution, but it was unclear if the lawyer swayed all of the conservative justices. The state warned against inmates being able to “avail themselves” of “endless procedure in state courts.”

The case puts a new focus on the testing of DNA crime-scene evidence and when an inmate can make a claim to access the technology in a plea of innocence. To date, 375 people in the United States have been exonerated by DNA testing, including 21 who served time on death row, according to the Innocence Project, a group that represents Reed and other clients seeking post-conviction DNA testing to prove their innocence.

Justice Elena Kagan seemed to agree with Reed’s attorney, saying it was important for the full appeals process to play out before an inmate asked a federal court to intervene.

“Isn’t the simplest thing just to say that the person isn’t harmed until the state process has come to an end and we know for a fact what the state judgment is?” she asked.

Justice Ketanji Brown Jackson also agreed, noting that if an inmate were to bring the challenge before the state proceedings were over, a federal court would likely move to put the appeal on hold until the state action concludes.

But Chief Justice John Roberts expressed concern at one point for inmates seeking to avoid an immediate appeal as a way to “put off” an execution.

For his part, Justice Brett Kavanaugh was interested in the “practical problems” courts would face if an inmate had to bring a federal court challenge before the state procedures were exhausted.

Court precedent allows a state prisoner who has been denied in state court to pursue a post-conviction claim for DNA testing in federal court. But Reed’s case raises a statute of limitations question about whether such a claim can be brought at the end of state court litigation or at the moment a trial court denied DNA testing.

Lower courts have split on the issue and the distinction is key for Reed as a federal appeals court ruled that he waited too long to bring his claim. How the Supreme Court rules could impact other death row inmates across the country seeking to test new evidence. And comes as DNA testing has become a more utilized means to exonerate those who have been wrongly convicted.

Reed has been on death row for the murder of 19-year-old Stacey Stites.

A passerby found Stites’ body near a shirt and a torn piece of belt. Investigators targeted Reed because his sperm was found inside her. Reed acknowledged the two were having an affair, but says that her fiancé, a local police officer named Jimmy Fennell, was the last to see her alive.

Reed claims that over the last two decades he has discovered a “considerable body of evidence” demonstrating his innocence. Reed claims that the DNA testing would point to Fennell as the murder suspect. Fennell was later jailed for sexually assaulting a woman in his custody and Reed claims that numerous witnesses said he had threatened to strangle Stites with a belt if he ever caught her cheating on him. Reed seeks to test the belt found at the scene that was used to strangle Stites.

The Texas law at issue allows a convicted person to obtain post-conviction DNA testing of biological material if the court finds that certain conditions are met. Reed was denied. He came to the Supreme Court in 2018 and was denied again. Now he is challenging the constitutionality of the Texas law arguing that the denial of the DNA testing violates his due process rights.

But the 5th US Circuit Court of Appeals held that he waited too long to bring the claim. “An injury accrues when a plaintiff first becomes aware, or should have become aware, that his right had been violated.” The court said that he became aware of that in 2014 and that his current claim is “time barred.”

Reed’s lawyers argued that he could only bring the claim once the state appeals court had ruled, at the end of state court litigation. In court, Parker Rider-Longmaid said that the “clock doesn’t start ticking” until state court proceedings come to an end. He said Texas’ reading of the law would mean that other procedures in the appellate process are “irrelevant.”

Janai Nelson of the NAACP Legal Defense Fund supports Reed arguing in briefs that the “overwhelming majority of incarcerated persons exonerated through DNA evidence since its introduction in 1989, have been people of color and primarily Black men.”

Texas Solicitor General Judd Stone II responded in court papers that at trial the state introduced “substantial” evidence that Reed had “sexually assaulted multiple other women.” Besides arguing that the suit is untimely, he also says that Reed’s claim cannot be brought because he lacks the legal right, or “standing,” to bring the case.

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Science

Meet the International Space Station’s new diverse crew

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A version of this story appeared in CNN’s Wonder Theory science newsletter. To get it in your inbox, sign up for free here.



CNN
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When astronauts venture aboard the International Space Station, they see a world without borders. They work together while orbiting Earth, and no boundaries are visible between them, even as member countries contend with geopolitics on the planet below.

This week, a SpaceX Crew Dragon spacecraft with a diverse crew lifted off from Kennedy Space Center in Florida.

The capsule carried NASA astronauts Nicole Mann and Josh Cassada, astronaut Koichi Wakata of the Japan Aerospace Exploration Agency, and cosmonaut Anna Kikina of Roscosmos — the first Russian to travel on a SpaceX spaceflight.

“We live in the same world, we live in the same universe,” Cassada said. “Sometimes we experience it in a very different way from our neighbors. We can all keep that in mind … and continue to do amazing things. And do it together.”

The NASA SpaceX Crew-5 mission, now safely ensconced on the space station, is one of firsts.

Nicole Aunapu Mann is the first Native American woman to go to space as well as the first woman to serve as mission commander for a SpaceX mission.

Mann grew up in Northern California and is a registered member of the Wailacki tribe of the Round Valley reservation. She has been a pilot and colonel in the US Marine Corps. But it wasn’t until her mid-20s that she realized she wanted to be an astronaut and that it was even possible.

“I realized that being an astronaut was not only something that was a possible dream but actually something that’s quite attainable,” Mann said. “I think as a young girl, I just didn’t realize that that was an opportunity and a possibility.”

A monster tsunami rippled across the planet when a dinosaur-killing asteroid crashed into Earth 66 million years ago.

The impact caused 75% of animal and plant life to go extinct and created a chain of cataclysmic events.

Waves more than a mile high pushed away from the impact crater near Mexico’s Yucatan Peninsula and scoured the ocean floor thousands of miles away from the asteroid strike. The tsunami was thousands of times more energetic than those generated by earthquakes.

Sediment cores also showed that the tsunami’s powerful force even disturbed coasts of New Zealand’s islands halfway around the globe.

We get by with a little help from our friends.

The James Webb Space Telescope recently teamed up with two other space observatories to produce dazzling new images of the cosmos. By working together, these telescopes can provide a more complete portrait of the universe.

The Chandra X-ray Observatory added X-ray data to some of Webb’s first images to reveal previously hidden aspects. The X-rays pinpointed exploded stars, a shock wave and superheated gas, all highlighted in glowing pinks, purples and blues.

Additionally, astronomers combined Webb and Hubble data to showcase a pair of galaxies about 700 million light-years away from Earth. Webb scientists also spied a celestial surprise, in the form of a distant galaxy, within the image.

Composting your produce scraps can be great for the environment, but there’s an art to this environmentally friendly practice.

Food waste creates harmful greenhouse gases inside a landfill — and little to none of it is composted. Composting means mixing food and yard waste with nitrogen, carbon, water and air to help scraps decompose and turn into fertile soil that your garden will love.

A compost pile that stinks isn’t getting enough oxygen and is emitting methane. To prevent the formation of this harmful gas, and the smell, turn your compost pile every two to five weeks.

Learn more about lifestyle changes to minimize your personal role in the climate crisis and reduce your eco-anxiety in our limited Life, But Greener newsletter series.

Swedish geneticist Svante Pääbo won the Nobel Prize for medicine this week for his pioneering use of ancient DNA to answer questions about human evolution.

In 2010, Pääbo sequenced the first Neanderthal genome and discovered that Homo sapiens interbred with them. Pääbo was also able to extract DNA from fossil fragments, which revealed Denisovans, a new kind of extinct human.

His work has allowed researchers to compare human genetics with the DNA of Neanderthals and Denisovans.

Meanwhile, the Nobel Prize for chemistry was awarded to scientists who discovered how to snap molecules together, and the Nobel Prize for physics went to quantum physicists for unlocking the eerie behavior of particles.

Check out these new finds:

— Archaeologists have uncovered the pieces of a nearly 2,000-year-old classical statue depicting the mythical hero Hercules in northeastern Greece.

— The Pacific Ocean is shrinking and making way for a new supercontinent, called Amasia, that will likely form in about 200 million to 300 million years.

— A new image from a telescope in Chile may look like a comet, but it’s actually an incredibly long debris trail created when the DART spacecraft slammed into an asteroid last month.

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US

He spent two decades in prison for church murders he didn’t commit. Newly discovered DNA evidence just helped exonerate him

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CNN
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A man who spent two decades in prison for a 1985 double homicide during church bible study has been exonerated, with all charges against him dropped.

Newly discovered DNA evidence from a hair sample shows Dennis A. Perry, 59, “may have been acquitted if that evidence had been available” during his 2003 trial for the murders of Harold and Thelma Swain in Georgia, according to a news release from Glynn County District Attorney Keith Higgins.

Stephen B. Morton/Atlanta Journal-Constitution/AP

Dennis Perry, center, standing beside wife Brenda Perry gets emotional while thanking the team from the Georgia Innocence Project after they worked to get his release after 20 years behind bars.

Perry, formerly of Camden County, Georgia, was sentenced to two consecutive life sentences following his arrest in 2000. His subsequent conviction was overturned in July, and Higgins’ office announced Monday that prosecutors will not re-try him.

“It took a long time, but I never gave up,” Perry said in a news release Monday. “I knew that eventually someone else would see the truth, and I’m so grateful to the Georgia Innocence Project and King & Spalding [law firm] for bringing the truth to light. This indictment has been hanging over my head for over 20 years, and it’s such a relief to finally not have to worry about being accused of this awful thing.”

The DNA evidence involves a pair of eyeglasses found at the crime scene in 1985, according to the news release. Investigators found that the glasses had two hairs belonging to the killer, stuck in the hinges.

In February 2020, private investigators working for Perry were able to get a hair sample from a Brantley County woman who is the mother of a man implicated, but not charged, in the 1985 Swain murders, according to the district attorney’s news release. Her hair sample was then examined by the same lab that did the DNA testing on the hair found in the eyeglasses in 2001 and those profiles matched, prompting the Georgia Bureau of Investigation to reopen the case in light of the new evidence.

Mitochondrial DNA testing was done using those hair samples prior to Perry’s 2003 trial and excluded him as a possible contributor of the hairs; however, he was convicted using circumstantial evidence at trial, the release said.

On the evening on their murders, the Swains were in bible study at Rising Daughter Baptist Church in Waverly, according to a news release from Georgia Innocence Project.

Before 9 p.m., an attendee left the meeting and found a man inside the church’s vestibule as she was leaving who asked to speak with Harold Swain, 66. She went back inside the prayer meeting to get him and left the church, Higgins’ news release said. Witnesses said they heard a “scuffle” followed by four gunshots.

Thelma, 63, heard the gunshots and ran to the vestibule – that’s when the killer shot her once. By the time the other meeting attendees ran to the back of the church, the killer had left.

The case quickly went cold, Higgins’ release said, but it was reopened by the Camden County Sheriff’s Office in 1998, according to a release from the Georgia Innocence Project.

Within a week, authorities identified Perry as the main suspect based mainly on testimony from an informant who wanted a $25,000 reward and ultimately was paid $12,000 in exchange for testimony – something that was never disclosed to Perry’s attorneys, the release from Georgia Innocence Project said.

Higgins said he consulted with the GBI and the victim’s family, and both agreed with his decision not to prosecute Perry.

“There are times when seeking justice means righting a wrong,” Higgins, who took office Jan. 1, said. “While this case was prosecuted prior to my administration, the new evidence indicates that someone else murdered Harold and Thelma Swain. Mr. Perry is now, and has been since July 2020, a free man. We will continue to examine all the evidence in the case — new and old — as we determine what the next step will be in this investigation.”

Since his release from prison, Perry has been spending time at home with his wife, Brenda, and reconnecting with friends and family, trying to recover and readjust to this new chapter of his life, the news release from Georgia Innocence Project said.

Thirty-six states and Washington, DC, have laws on the books that offer compensation for exonerees, according to the Innocence Project. Georgia isn’t one of them.

The federal standard to compensate those who are wrongfully convicted is a minimum of $50,000 per year of incarceration, plus an additional amount for each year spent on death row. Of the 36 states with compensation laws, nine offer more than $50,000 per year – including Washington, which offers $200,000 per year, according to the Innocence Project.

Late last month, Democratic Rep. Maxine Waters of California introduced the Justice for Exonerees Act, which would amend the federal statute to increase the compensation amount to a minimum of $70,000 per year.

CNN’s Rebekah Riess and Chenelle Terry contributed to this report.

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