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Genetic Linkage

Wishbone Day Raises Awareness of Osteogenesis Imperfecta

Today, May 6th, is Wishbone Day, to raise awareness about osteogenesis imperfecta (OI).

 

Also known as "brittle bone disease," OI is a consequence of mutations that disrupt the highly organized structure of collagen, a major component of connective tissues. Collagen accounts for more than half the protein in bone and cartilage, and is also part of skin, ligaments, tendons, and the dentin of teeth.

 

Because OI is due to a deficit of collagen, eating more calcium doesn't help – the advice given to members of a family I wrote about here. Before many genes behind OI were identified, some parents of children with OI were suspected of child abuse, especially when a second child had fractures too.

 

A Collection of Collagen Conditions

 

To continue reading, go to DNA Science, my blog at Public Library of Science.

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Genomics to the Rescue for Sumatran Rhinos

Kertam, a Sumatran rhinoceros

Sumatran rhinoceroses are solitary creatures that browse the dense rainforests of Borneo and Sumatra, living in small, scattered, shrinking groups. Taking a census is challenging, although they "sing." It isn't known how many of them exist, exactly, but the number is small.

 

A multinational research team has unearthed clues in the genomes of 21 of the animals, five "historical" from the Malay Peninsula where they are extinct, and 16 modern genomes from the remaining populations on Sumatra and Borneo. "Genomic insights into the conservation status of the world's last remaining Sumatran rhinoceros populations" appears in Nature Communications.

 

 

To continue reading, go to DNA Science, where this post first appeared.

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Expand Rapid Testing to Help Counter COVID Variant Spread, Says Harvard Epidemiologist Michael Mina

I just returned from an enlightening trip to CVS, to photograph Abbott Lab's at-home rapid antigen test for COVID, BinaxNOW. It became available at three major drugstore chains on April 19.

 

"Do you have the rapid COVID test? The at-home one?" I asked the woman behind the pharmacy counter.

Deer-in-the-headlights.

 

Fortunately, the pharmacist behind her overheard. "Not only don't we have it, but we don't know when we'll be getting it." I wasn't too surprised; I live in a small town.

 

So I got on line to buy some vitamin gummies, appropriately socially distanced, and saw to my immediate left a prominent display of items that everyone should have to prevent COVID: wipes, hand sanitizer, gloves, masks. They provided a backdrop to a stack of 6 boxes of – BinaxNOW!

 

Of course, a detection test to see if you've been infected is not at all the same thing as a preventive measure. So I circled back to the pharmacy, and within seconds of notifying the pharmacist that the tests were indeed available, an angry summons for the manager bellowed out over the loudspeaker.

 

Oops.

 

 

To continue reading, go to DNA Science, where this post first appeared.

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Would you agree to be infected with COVID for science? Intentional 'challenge' studies underway as researchers explore new vaccines and treatments

(hVIVO)

Lauren Thomas, who just turned 26, is trying to get into a clinical trial at the University of Oxford, where the American is in a master's program in data science. She's seeking to be intentionally reinfected with SARS-CoV-2, the virus that caused her bout with COVID-19 back in October.

 

Thomas had a mild case – just a fever. So now she's volunteering to help researchers understand the aftermath of infection, waiting to hear whether she'll get into the clinical trial. In the meantime, she's an organizer for 1daysooner, a non-profit advocacy group for people wishing to participate in research and launched in April 2020. A major focus has been joining clinical trials for COVID vaccines.

 

Why would anyone sign up for a second encounter with the virus that has shattered the world?

 

To continue reading, go to Genetic Literacy Project, where this post first appeared.

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3 Possible Origins of COVID: Lab Escapee, Evolution, or Mutator Genes?

B.1.1.7 variant (NIAID)

"Virus outbreak: research says COVID-19 likely synthetic," shouted the headline in the Taipei Times on February 23, 2020. The idea that the novel coronavirus SARS-CoV-2 arose in a virology lab in China – by accident or as a bioweapon – has sparked an undulation of accusation and explanation ever since.

 

The latest chapter: An "open letter" in the April 7, 2021 New York Times, calling for "a full investigation into the origins of COVID-19." The two dozen scientists who signed the letter cite the continuing absence of a "robust process" to examine critical records and biological samples. Their argument responds to the WHO's March 20 press event that barely considered an origin other than from a natural spillover.

 

But two types of new information may counter the lab escapee hypothesis: filling-in-the-blanks of mammals that may have served as "missing links" in the evolution of disease transmission, and the rapid rise of viral variants reflecting a tendency to mutate that may underlie SARS-CoV-2 seemingly bursting from out of nowhere.

 

So here is my view, as a geneticist, of three possible origins of SARS-CoV-2:

 

1. Bioweapon – an engineered pathogen or escape of a natural candidate

 

2. Gradual evolutionary change through intermediate animal hosts, mutating along the way and becoming more virulent

 

3. "Mutator" genes that trigger mutations in other genes, speeding evolution

 

To continue reading, go to my blog DNA Science at Public Library of Science.

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Huntington’s Disease: 2 Steps Backward, 1 Step Forward

Last week's DNA Science post considered the ebb and flow of treatment possibilities for Alzheimer's disease. This week, it's Huntington's disease.

 

Like Alzheimer's, the less familiar HD also affects the brain, but HD is always inherited and is much rarer. The only treatments for HD manage symptoms, some of them prescribed off-label, borrowed from other conditions. A treatment that addresses the underlying cause of the disease, which delays onset or slows progression, has been elusive for decades.

 

A Disease Like No Other

 

HD is one of 40 "expanding repeat" diseases. A tiny part of a gene repeats many times, resulting in an encoded protein burdened with extra amino acids that interfere with its folding, rendering the protein sticky. In HD, mutant huntingtin protein gums up neurons in the brain's striatum, blocking signals essential to control movements and to think. Behavior changes too – anger and aggression may soar, as irritability, loss of impulse control, and confusion reign. The white matter part of the brain – the axons of those neurons – shrinks.

 

To continue reading, go to DNA Science, where this post first appeared.

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Alzheimer’s Treatments in the Pipeline and the False Promise of Prevagen: Distinguishing Hope from Hype

 
 
 

The avalanche of TV ads for Prevagen that coincided with my reaching Medicare age has inspired me to investigate what's coming for Alzheimer's disease (AD) – real treatments. Prevagen is not that.

 

Deceptive Advertising

 

The scenes, unending lest they immediately vanish from the viewer's disintegrating memory, show gorgeous older folks, especially couples, enjoying life and claiming that Prevagen keeps them thinking clearly, implying that they wouldn't have otherwise. A banner on the lower right proclaims "Prevagen improves memory." Yet there's no evidence that this is in fact true.

 

Prevagen pitches don't mention the class action lawsuit against Quincy Bioscience that was settled in 2020. Customers who had their receipt could get $70 back, and those who didn't, a generous $12. The red flag? Those claims to improve memory.

 

Prevagen, a "brain health supplement" and not a drug, falls into that regulatory backwater for products skirting rigorous clinical trials. The settlement demanded the company stop the claims, but "Buy Prevagen® Brain Health & Memory Improvement Supplements" appears instantly on Google. The asterisk above "Supplements" is the standard disclaimer: "These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease."

 

To continue reading, go to my DNA Science blog at Public Library of Science, where this post first appeared.

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Science Writing in the Age of COVID-19

It's been a strange and busy 15 months for science journalists.

 

Each day, throughout the day, our inboxes overflow with the latest from the technical medical and science journals – tables-of-contents, abstracts, news releases, and the never-ending stream of article preprints. We jumpstart the journals by going straight to medRxiv and bioRxiv, aka "med-archive" and "bio-archive," where investigators post articles before peer review.

 

Where We Get Information

 

It's a deluge, an unrelenting barrage of new reports from the Science and Nature family of journals; the medical journals like JAMA, the Lancet group, and the NEJM; and publications that cover more basic science, like Cell and the journals from Public Library of Science, which has sponsored this blog since 2012. The journals send wrap-ups on the weekends, in case we've missed anything.

 

The clearinghouse for news releases for journalists, Eurekalert, provides information from a wide range of publications, government agencies, academic institutions, research centers, nonprofits, and companies, with quotes from experts and images and videos we can use. Eurekalert added a COVID tab to the topics menu early in the pandemic. Much appreciated!

 

As we try to stay ahead of our inboxes, we're invited to webinars, zooms, and podcasts, all wonderfully helpful in crafting our stories.

 

To continue reading, go to my DNA Science blog at Public Library of Science, where this post first appeared.

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On the Anniversary of the Pandemic, Considering the Bioweapon Hypothesis

A year ago, the Director General of the World Health Organization, Tedros Adhanom Ghebreyesus, delivered the message that would divide time:

 

"WHO has been assessing this outbreak around the clock and we are deeply concerned both by the alarming levels of spread and severity, and by the alarming levels of inaction. We have therefore made the assessment that COVID-19 can be characterized as a pandemic."

 

What followed was a call to action to all. "We have rung the alarm bell loud and clear." And instantly, the redundant "global pandemic" ricocheted across the media, reverberating still.

 

The name of the enemy had changed quickly as 2020 began, from the "Wuhan coronavirus" to "2019 novel coronavirus" shortened to "2019-nCoV," and finally to SARS-CoV-2, acknowledging similarity to SARS, circa 2003-2004.

 

Whatever it's name, did SARS-CoV-2 have an older guise, perhaps in a lab?

 

The Bioweapon Hypothesis

 

To continue reading, go to DNA Science, where this post first appeared.

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Is COVID Optimism Finally Overtaking Pessimism? Harvard Experts Weigh In

Glimmers of hope are beginning to shine through the gloom of the past year. That was evident in a recent webinar that the Massachusetts Consortium on Pathogen Readiness (MassCPR) held to "demystify" the new viral variants. Each consists of several mutations.

 

Will the variants fuel "a novel stage of contagion, COVID 2.0?" opened George Daley, MD, PhD, dean of Harvard Medical School. "What has been unsettling is how many times mutations have cropped up independently in infected patients across the globe and in petri dishes. This is a consequence of Darwinian evolution by natural selection in real time," he added. The fact that the virus, SARS-CoV-2, has mutated in the same ways at different times and places suggests that the changes benefit the virus.

 

Also disturbing is that once variants appear, they proliferate. "That suggests the virus is more contagious, or replicates faster, so that it takes over the outbreak," said Jeremy Luban, MD, from the University of Massachusetts Medical School. Most mutations are neutral; we need to worry when they combine into "variants of concern," aka VOC. "They could permit the virus to escape immune control that's been established in a person from prior infection or from a vaccine," Luban added.

 

The "big three" variants of most concern now have hard-to-remember numerical names, which avoid stigmatizing a place: B.1.3.5.1 variant (South Africa), B.1.1.7 (UK), and P.1 (Brazil). The last one may be the worst to arise, so far. It first came to attention in Manaus, Amazonia. "Up to 70% of the population had been infected and they had developed what we'd consider herd immunity that would prevent new infection," Luban explained. The explosion of hospitalizations and deaths in December, a second wave, coincided with the appearance of the P.1 variant. "Many mutations in it raise concerns about whether the virus is resistant to the immune response against the first virus," he added.

 

Tackling variants requires asking three questions, Luban said:
• Do they enhance transmission?
• Do they permit reinfection?
• Do they decrease vaccine efficacy?

 

Fortunately, the vaccines so far are doing their job. Here are 6 pieces of good news.

 

To continue reading, go to DNA Science, where this post first appeared. 

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