Ricki Lewis's Blog, page 10

DNA Analysis Solves the Mystery of the Rabbit Invasion of Australia

COVID and monkeypox seem to have come out of nowhere and exploded across continents. But the phenomenon of natural selection acting on genetic variants – of viruses or organisms – that have an advantage in a certain place and time is ages old. The rabbits of Australia provide a powerful example of natural selection run amok, favoring a particularly robust mix of domestic and wild traits against an environmental backdrop of plenty of food and a paucity of predators.

 

The animals that have overrun the continent eat almost any plant, their appetites reverberating along food webs, costing an estimated $200 million a year. Over decades, interventions to control their numbers – from rabbit-proof fences to intentional infections with nasty viruses to shooting – have all failed. "In Australia, the rabbit has survived drought, fire, flood, diseases, predators, poisons and other stratagems devised by man and remains this country's most serious vertebrate pest," wrote Brian Coman in "Tooth and Nail: The Story of the Rabbit in Australia."

 

Now researchers from the University of Cambridge and CIBIO Institute in Portugal have wed genetics to history to illuminate the precise source of Australia's problem. Their report is in the Proceedings of the National Academy of Sciences.

 

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

Can Curcumin, Black Pepper, and Ginger Treat Retinitis Pigmentosa? Steve Fialkoff’s Excellent Experiment

Steve Fialkoff and I weren't friends at James Madison High School in Brooklyn, NY. We were in the class of 1972; earlier alums include Chuck Schumer, Bernie Sanders, and Carole King. The near-thousand of us self-sorted into three cliques, based on neighborhood. Steve was from Mill Basin, me Kings Highway.

 

While super-popular Steve was everywhere with his massive blond 'fro, capturing our experiences with his camera and leading the class in drama productions, I was on the fast track to nerddom. I spent my time in the chem lab with the groovy new teacher in charge, a 24-year-old who showed my bestie Wendy and me how to make bongs and water pipes. But Steve now says he was a closet nerd, a "frizzy-haired, freckle-faced, big-nosed, crooked-smile, toothy guy."

 

It wasn't surprising that Steve became a film editor and now a playwright. What was surprising was learning at age 25 that he had retinitis pigmentosa, after he tripped over a seat in a darkened theater and had a few other stumbles.

 

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

Mellow Yellow: A Biotech Way to Make Saffron

Biotechnology mass-produces valuable molecules from nature, from drugs to textiles to a jellyfish protein that lights up most anything a glowing green. Now add saffron to the list.

 

To cooks, saffron is a bright yellow spice derived from Crocus sativus flowers, aka "saffron crocus." The dried red threads at the blooms' centers are used to season and color foods. Popular for thousands of years, saffron comes today mostly from Iran. It's used to infuse meats, grains, salads, and even to color marshmallows molded into baby chick shapes for Easter.

 

Saffron has medicinal potential. The main pigment crocin may be useful as a neuroprotectant, an antidepressant, a sedative, and an antioxidant.

 

Inspiring a Song

To those of us of a certain age, the word "saffron" conjures up "mellow yellow," a 1966 song by Donovan:

 

I'm just mad about saffron
A-saffron's mad about me …
They call me mellow yellow …

 

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

Thoughts on a Return of Polio

When a case of polio showed up in Rockland county, just north of New York City, in July 2022, and then polioviruses with the same genetic sequence as from the paralyzed man were found in three samples of wastewater collected from near his home, public health officials were alarmed. The man, from an Orthodox Jewish community with low vaccination rates in general, had not been immunized against polio.

 

Definitions from the World Health Organization kicked in.

 

The viral RNA sequence from the patient was close to that of oral polio vaccine, which is "live" (weakened, aka attenuated). He was infected with vaccine-derived polioviruses (VDPV). Then finding the telltale RNA sequence in wastewater elevated the situation to circulating vaccine-derived polioviruses (cVDPV). The US now joins 30 other nations experiencing a return of this infectious disease that was once thought to be nearly gone.

 

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

Two Newly-Approved Gene Therapies Cost Millions

The FDA recently approved two gene therapies with hefty price tags, the first for an inherited anemia and the second for a degenerative brain condition. The two new treatments, from bluebirdbio, double the number of gene therapies on the market.

 

Most biotechnologies evolve over three decades or so, but the idea of gene therapy has been around since the late 1950s, blooming soon after Watson and Crick solved the structure of DNA. When my book The Forever Fix: Gene Therapy and the Boy Who Saved It was published a decade ago, it would still be 5 years before the first approval. That treatment, the subject of my book, enabled the blind to see, sometimes in just days.

 

Why has the pace of gene therapy been so slow? Cost is one barrier. Other concerns are the degree to which a gene therapy actually helps, how long the effect lasts, and what proportion of patients respond.

 

A Short List

 

FDA's gene therapy roster is here, but a caveat is necessary.

 

 

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

Did a Virus Type Used in Gene Therapy Cause the Recent Wave of Hepatitis in Kids?

The last thing the field of gene therapy needs is another setback. Two studies, not yet peer-reviewed, point to adeno-associated virus (AAV) as a suspect behind the unusual hepatitis that emerged in children in April 2022.

AAV has been critical to the development of gene therapy, as carriers of human genes in the single strand of DNA that is the viral genome.

 

AAV has been considered relatively harmless, as viruses go. It was discovered in 1965 as a tiny tag-along that will only replicate in human cells if adenovirus is also there at some point – hence the "adeno-associated." AAV infection can also accompany certain herpes infections. Several subtypes of AAV have since been identified; AAV2 and AAV9 are gene therapy favorites. And they're common. Eighty percent of us harbor AAV2.

 

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

OrganEx Revives Pigs an Hour After Death, Holding Promise for Transplants

Transplant medicine could take a giant leap forward if donor organs could soak up oxygen for longer and decay delayed. A technology called OrganEx, described in Nature from a team at Yale, promises to do just that. The researchers stopped the hearts of pigs and an hour later used OrganEx, then cataloged the return of bodily functions. The new approach far exceeded the ability of existing technology to prolong organ viability.

 

Popular Pigs

Pigs have long been a popular animal model of human disease because they are about our size and their hearts and blood vessels are quite similar. They have also had fictional roles in medicine.

 

 

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

Where Will the Next Pandemic Come From? Highlights from CDC’s Emerging Infectious Diseases

When monkeypox came from out of nowhere in the spring, it sounded like a joke to our collective COVID-fatigued brains. I think we've all got CDC fatigue too. When revised recommendations recently told us it was okay to do or not do what we've been doing or not doing for months, I don't think many people paid attention. I'm glad the agency is finally re-evaluating things.

 

What may not be as well known is that CDC publishes an excellent, open-access, international, peer-reviewed monthly journal, Emerging Infectious Diseases. Since 1995, EID has provided a window into future health concerns, for us and other animals, with historical and cultural background as well as current epidemiology, covering all sorts of things.

 

Underlying the research reports on eclectic infectious diseases in the journal are a set of shared and converging factors:
• global climate change shifting habitats
• metagenomics technology comparing genome sequences in environmental samples
• perhaps we're looking harder
• a much more epidemiologically literate public than pre-pandemic

 

So I thought I'd investigate the August 2022 issue of EID. The focus is zoonoses – diseases that jump from non-human animals to us.

 

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

Revising my genetics textbook: A PC exercise or an appropriate evolution of science and sensitivity? Or both.

Beyoncé is facing a lot of criticism for using an ableist slur in her new co-written song Renaissance. She used the word "spaz" twice in a derogatory reference to a neurological disorder in Heated, which dropped in late July.

 

Just a few weeks before, while promoting her new song GRRLS, Lizzo used the same slur. The tweet went viral, prompting a sharp rebuke by Hannah Diviney, who has cerebral palsy. Her tweet also viral, landed on the front page of the BBC, New York Times and the Washington Post. 

 

Lizzo took notice and changed the lyrics. "I never want to promote derogatory language," she wrote.

 

I've lapsed too in word choices, but I'm not a pop star – I write college life science textbooks. I'm currently revising the 14th edition of my human genetics textbook. I've written or co-written four textbooks, totaling 38 editions: intro biology, human anatomy and physiology, and human genetics. Other authors have taken over all but human genetics: I update it every three years. 

 

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

Jurassic World: Dominion Bashes Biotech

If a new Planet of the Apes or Jurassic Park film comes out, I'm going to go see it. The latest, Jurassic World:Dominion, didn't disappoint.

 

A Plague of Locusts

 

The science is mostly accurate, the bioethics message obvious, and the plot adheres to Isaac Asimov's "change one thing" rule for science fiction. In the world of Jurassic Park, that lone variable is time. We just have to accept that a "titanosaur" like Argentinosaurus somehow grew and developed from a lab-nurtured baby to a 130-foot-tall and 110-ton adult in a few years.

 

The official summary from IMDb for the new film is vague and continues the impossibly-rapid-growth theme:

Four years after the destruction of Isla Nublar, dinosaurs now live–and hunt–alongside humans all over the world. This fragile balance will reshape the future and determine, once and for all, whether human beings are to remain the apex predators on a planet they now share with history's most fearsome creatures in a new Era.

 

Four years? Animals radiating around the world? Even rats or rabbits couldn't do that. And the film is actually more about insects.

 

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