Ricki Lewis

Whenever I work on a new edition of my human genetics textbook and reach the section on eugenics, which flourished in the United States in the 20th century well into the 1930s, I'm relieved that it's history. But in the summer of 2017, as I wrapped up the 12th edition, the eugenics coverage took on a frightening new reality with the attack in Charlottesville, where white supremacists bellowed "Jews will not replace us!" A president noted at the time, "there are very fine people on both sides."

It's now 2022. I've just finished revamping the section in my textbook on eugenics for the 14th edition. And once again, eugenics is in the headlines, with the attack on Black shoppers at a supermarket in Buffalo, New York. 

As another president once said, "here we go again."

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

Tales of time travel have intrigued me since The Time Machine film scared the crap out of me at my cousin Ron's ninth birthday party. Now The Time Traveler's Wife, a novel from 2003 and film from 2009, has resurfaced in series form on HBO.

Emily St. John Mandel's new novel Sea of Tranquility also follows a time traveler, across five centuries. The tale begins in 1912 in Canada and ends, if you look at time as linear rather than looped, in a dark, domed moon colony. The author wrote Station Eleven, so I was thrilled that she has a new book. Although it's fiction, events during the middle time period unfold during a pandemic. It is an eerily familiar backdrop.

The Star Trek Futuristic Precedent

The #1 rule of time travel: you can't go back and change anything. A poignant demonstration of this edict is "The City on the Edge of Forever," considered by some to be the best installment of any Star Trek series ever. It was the penultimate episode of the first season, debuting on NBC on April 6, 1967 and written by Harlan Ellison.

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

When I was growing up in the 1960s, chewing gum was a big deal.

TV ads showcased the doublemint twins and their stick gum, and the small squares of chiclets. Kids preferred tiny bricks of pink Bazooka with the folded-up shiny papers bearing dumb comics. Girls collected rectangular

Juicy Fruit wrappers, folding them thrice in two dimensions and linking them into loooong chains that we'd save for our future first boyfriends.

We had tea-flavored teaberry gum, and a yummy licorice one with a name that is probably no longer politically correct.

Trident gum offered a sugar-free option, while Dentyne gave the illusion of health. New York City pharmacist Franklin V. Canning invented the gum in 1899, formulated to "sweeten the breath, to keep teeth white," according to the wrapper. Dentyne cleverly combines "dental" and "hygiene."

And an ancient song was entitled, "Does your chewing gum lose its flavor on the bedpost overnight?"

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

I've long been fascinated with the 1918 influenza pandemic because my grandfather Sam survived it. He married his nurse, lived 103 years, and likely had lifelong B cells that held the memory of his encounter with the flu. I wrote "A 1918 Flu Memoir" about him in 2008 for The American Journal of Bioethics.

We know very little about the 1918 pandemic flu, other than what it did to millions. The virus wasn't even identified until 1933. Compare that to the deluge of SARS-CoV-2 genome sequences posted daily, nearly 11 million as I write this.

What we do know about the 1918 flu comes from bits of lung tissue from museum specimens or preserved in permafrost.

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

I originally published When Does a Human Life Begin? 17 Timepoints here at DNA Science in 2013. My intent was to inform those who confuse embryo with fetus with baby by presenting how biologists describe human prenatal development – beginning at fertilization. Human gestation is on average 38 weeks, not 40, according to biology.

I rerun "17 Timepoints" periodically to counter assaults on woman's reproductive rights – which unfortunately happens with disturbing regularity.

In 2017, I reposted when The Federalist published "Life Begins at Conception, Says Department of Health and Human Services."

Then in September 2021, Genetic Literacy Project reran "17 Timepoints" with the updated headline (which I didn't write) Viewpoint: 'The fetus is 1/25th of an inch' — Texas abortion ban bungles the science on when human life begins, contends biologist and professor.'

And along the way, various right-to-lifers have responded to my post with insults to my expertise, but no sign of actually understanding the biology. So it goes …

Now the rerun of "17 Timepoints" is in response to the leaked Supreme Court document threatening Roe v Wade, published in Politico and written by Josh Gerstein and Alexander Ward. To paraphrase Ronald Reagan, here we go again.

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

The sudden inability to smell and taste that comes with COVID is startling and difficult to describe. I was lucky to experience it only for a few days.

Anosmia is the partial or total loss of the ability to smell, which vanquishes most of the sense of taste, too. The COVID version is more profound than the familiar dulling of the sense from the mucus of a common cold. And it has a different origin.

The odd part of COVID anosmia is that the virus alters gene expression in nerve cells in the nose – even though the virus can't actually enter nerve cells (neurons). Then the temporarily crippled cells can't signal the brain that the person is inhaling near the seashore or passing a garbage dump. Understanding the basis of the secondhand assault may clarify other puzzling effects of the changeling coronavirus – perhaps even long COVID.

Clever experiments recently revealed how COVID anosmia happens. Benjamin R. tenOever and colleagues from the NYU Grossman School of Medicine and Columbia University report their work using golden hamsters and the noses of human corpses in Cell.

First, a closer look at how the sense of smell works.

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

The Roma people have long held a special fascination for population geneticists who study the frequencies of genetic diseases. The largest minority in Europe, the Roma number 10 to 12 million and live in scattered groups, mostly in central and southeastern Europe. A recent Comment in Nature, from a team at the University of Freiburg, explores how "Europe's Roma people are vulnerable to poor practice in genetics."

A Tragic History

The Roma, once called gypsies, likely originated in the Punjab region of northwest India about 1,500 years ago. They traveled to Persia (Iran), then through Armenia to the Balkan peninsula, and reached the Iberian peninsula by the 15th century. Their genomes diversified as people joined along the way. After their arrival in Portugal and Spain, persecution began. It was the beginning of extreme discrimination and isolation that would unfold over the years.

The Roma and the Jews became the targets of the Nazi goal of "racial hygiene." In 1936, investigators at The Race Hygiene and Population Biology Research Centre drew pedigrees of these groups to form the rationale of a "scientific basis" for the "final solution." German geneticists studied the Roma. Ferdinand Sauerbruch, nominated for a Nobel, submitted a grant proposal to conduct "genetic and medical research" in Auschwitz, which the Deutsche Forschungsgemeinschaft funded. Hundreds of thousands of Roma died in experiments.

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

I often marvel at the disconnect between media coverage of "breakthrough" treatments and the decades of research that lie behind them. A new drug is the culmination of basic research, preclinical experiments on animals and cells, three phases of clinical trials, and post-marketing surveillance. It takes decades.

A small, phase 1 study – safety in healthy people – caught my attention this week. The work was presented at the American College of Cardiology's annual meeting and published online in the Journal of the American Medical Association.

The healthy participants had elevated levels of apolipoprotein(a), which is made in the liver and goes to the blood, where it carries cholesterol. High levels raise risk of heart attack, stroke, and narrowing of the aorta. Could silencing the gene that encodes the protein portion of apolipoprotein(a) lower the level, perhaps even preventing the heart disease?

One way to silence a gene uses a natural process, RNA interference (RNAi), which blocks translation of a gene's information into construction of a specific protein. The first drug using RNAi was Onpattro, approved in 2018 to treat a rare form of amyloidosis. The disease causes tingling, tickling, and burning sensations and affects about 3,000 people in the US.

In the new study, the researchers injected tiny pieces of short interfering RNAs (siRNAs), which glommed onto the messenger RNAs for the protein part of apolipoprotein(a). The 32 healthy volunteers received placebo or ascending doses. Levels of apolipoprotein(a) fell in a dose-dependent manner, by about 98 percent for the highest-dose group. All doses were well tolerated and the lowering largely persisted when checked at five months.

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

I pity the 15 percent of the human population that cannot live with a cat, due to allergy. I've seen it happen, a guest's face blowing up. My best friend Wendy can visit here, where cats outnumber people two-to-one, only by megadosing on antihistamines and heading to the porch to breathe periodically. Even with that she's good for only a day or two.

But CRISPR gene editing may come to the rescue, someday.

Snip out the gene that encodes a protein called Fel d 1, and the kitty can no longer make a hapless human's eyes and nose run and bronchioles constrict in an asthma attack. That's what Nicole F. Brackett and a team from InBio have done in cat cells. Their work was just published in The CRISPR Journal. (If googling makes this news seems recycled, it's because an abstract appeared just before the world shut down in early 2020.)

CRISPR is a tool that can remove, replace, or add a selected bit of DNA to a chromosome. To counter cat allergy, CRISPR would delete the genes that encode the offending allergen.

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