Some ‘Junk DNA’ Serves a Purpose


By YASEMIN SAPLAKOGLU
If you stretched out all the DNA in a single human cell, it would be more than 6 feet long. But only a sliver of that DNA makes proteins, the biological machinery for life. In 2003, the Human Genome Project quantified just how little: Only 1% to 2% of our DNA — about 1.5 inches out of those 6.5 feet — encodes genes for protein. The noncoding sequences that make up the other 98% are often referred to as “junk DNA,” a term coined in 1972 by the geneticist Susumu Ohno, who suggested that just as the fossil record is full of extinct species, our genomes are full of extinct or badly copied genes damaged by mutations.
 
But even though 98% of the genome is noncoding, it isn’t precisely dead weight. In 2012, a consortium of hundreds of scientists reported in the Encyclopedia of DNA Elements that at least 80% of the genome is “active” in the sense that some of the DNA is being translated into RNA, even if that RNA isn’t then being translated into proteins. There’s little evidence that most of this RNA from broken genes does anything.
 
However, some of the noncoding sequences, making up roughly 8% to 15% of our DNA, aren’t junk at all. They serve important purposes, regulating which genes in cells are active and how much protein they produce. Researchers are still discovering new ways that noncoding DNA does this, but it’s clear that human biology is massively influenced by the noncoding regions, which don’t directly code for proteins but still mold their production. Mutations in these regions, for example, have been linked to diseases or disorders as varied as autism, tremors and liver dysfunction.
 
Moreover, by comparing human genomes to those of chimpanzees and other animals, scientists have learned that noncoding regions may be a big part of what makes us uniquely human: It’s possible that gene regulation by noncoding DNA differentiates species more than genes and proteins themselves do.
 
Researchers are also finding that new mutations can sometimes confer new abilities on noncoding sequences, which makes them a kind of resource for future evolution. As a result, what deserves the label “junk DNA” can be controversial. Scientists have clearly started to clean out the junk drawer since 1972 — but how much to keep in there is still up for debate.

What’s New and Noteworthy

Scientists have been working to understand a type of noncoding DNA known as “transposons” or “jumping genes.” These snippets can hop around the genome, making copies of themselves that sometimes get inserted into sequences of DNA. Transposons have increasingly been found to be critical to tuning gene expression, or determining which coding genes get turned on to be transcribed into proteins. In part for that reason, they are proving to be important to an organism’s development and survival. When researchers engineered mice to lack transposons, half of the animals’ pups died before birth. Transposons have left marks on the evolution of life. Quanta has reported that they can jump between species — such as from herring to smelt and from snakes to frogs — sometimes even providing some kind of benefit, such as protecting fish from freezing in ice-cold waters.
 
Geneticists are also investigating “short tandem repeats,” in which a stretch of DNA only one to six base pairs long is heavily repeated, sometimes dozens of times in a row. Scientists suspected that they help regulate genes because these sequences, which make up about 5% of the human genome, have been linked to conditions like Huntington’s disease and cancer. In a study covered by Quanta in February, researchers unraveled one possible way that short tandem repeats could regulate genes: by helping to convene transcription factors, which then help turn on the protein-making machinery.
 
Then there are “pseudogenes,” the remnants of working genes that were duplicated and then degraded by subsequent mutations. However, as Quanta reported in 2021, scientists have been finding that sometimes pseudogenes don’t remain pseudo or junk; instead, they evolve new functions and become genetic regulators — sometimes even regulating the very gene from which they were copied.

Quanta Magazine News Letter

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“How the Movie ‘Civil War’ Echoes Real Political Anxieties” By Lisa Lerer

“Civil War” has tapped into a dark set of national angst. In polls and in interviews, a segment of voters say they fear the country’s divides may lead to actual, not just rhetorical, battles.

One subject seems to be unifying the right and the left today: Disunion.

From the multiplex to social media, the prospect of America collapsing into armed conflict has moved from being an idea on the tinfoil-hat fringes to an active undercurrent of the country’s political conversation.

Voters at campaign events bring up their worries that political division could lead to large-scale political violence. Pollsters regularly ask about the idea in opinion surveys. A cottage industry has arisen for speculative fiction, serious assessments and forums about whether the country could be on the verge of a modern-day version of the bloodiest war in American history.

And “Civil War,” a dystopian action film about an alternative America plunged into a bloody domestic conflict, has topped box office sales for two consecutive weekends. The movie has outperformed expectations at theaters from Brownsville, Texas, to Boston, tapping into a dark set of national anxieties that took hold after the Jan. 6, 2021, storming of the Capitol.

But Barbara F. Walter, a political scientist at the University of California, San Diego, who studies civil wars, says the prospect of such a conflict isn’t just metaphorical. She believes the country is facing a decade or two of political instability and violence that could include assassinations of politicians or judges and the rise of militia groups.

The movie’s realistic portrayal of such violence taking place in deeply American settings — a golf course, a roadside gas station, the Lincoln Memorial — put the scenes of violence Americans associate more with foreign conflicts into sharper relief, she said.

David W. Blight, a historian at Yale University who specializes in the Civil War period, said he did not believe the country stood on the precipice of another one. But if the country were to reach that point, he said, the conflict could share more with the movie version than the historical one.

“For the last couple of years, there’s been all this chatter and a few books out about whether the U.S. is on the brink of a new civil war, and you have to keep telling people, ‘Well no, not in the way you may think about it,’” he said. “Our real Civil War blinds us in that sense.”

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” American Evangelical Christins-Fundamentalism, Evangelicalism and Pentecostalism” By David French

( Great article to understand American Christians and which Christian group is strong supporter of Trump)

In reality, American evangelicalism is best understood as a combination of three religious traditions: fundamentalism, evangelicalism and Pentecostalism. These different traditions have different beliefs, different cultures and different effects on our nation.

The difference between fundamentalism and neo-evangelicalism can be summed up in two men, Bob Jones and Billy Graham. In a 2011 piece about the relationship between Jones and Graham, the Gospel Coalition’s Justin Taylor called them the “exemplars of fundamentalism and neo-evangelicalism.” Jones was the founder of the university that bears his name in Greenville, S.C., one of the most influential fundamentalist colleges in America.

Bob Jones University barred Black students from attending until 1971, then banned interracial dating until 2000. The racism that plagued Southern American fundamentalism is a key reason for the segregation of American religious life. It’s also one reason the historically Black Protestant church is distinct from the evangelical tradition, despite its similar views of the authority of Scripture.

Graham attended Bob Jones University for a semester, but soon left and took a different path. He went on to become known as “America’s pastor,” the man who ministered to presidents of both parties and led gigantic evangelistic crusades in stadiums across the nation and the world. While Jones segregated his school, Graham removed the red segregation rope dividing white and Black attendees at his crusades in the South — before Brown v. Board of Education — and shared a stage with Martin Luther King Jr. at Madison Square Garden in 1957.

But since that keen Jones/Graham divide, the lines between evangelicalism and fundamentalism have blurred. Now the two camps often go to the same churches, attend the same colleges, listen to the same Christian musicians and read the same books. To compound the confusion, they’re both quite likely to call themselves evangelical. While the theological differences between fundamentalists and evangelicals can be difficult to describe, the temperamental differences are not.

Roughly speaking, fundamentalists are intolerant of dissent. Evangelicals are much more accepting of theological differences. Fundamentalists place a greater emphasis on confrontation and domination. Evangelicals are more interested in pluralism and persuasion. Fundamentalists focus more on God’s law. Evangelicals tend to emphasize God’s grace. While many evangelicals are certainly enthusiastic Trump supporters, they are more likely to be reluctant (and even embarrassed) Trump voters, or Never Trumpers, or Democrats. Fundamentalists tend to march much more in lock step with the MAGA movement. Donald Trump’s combative psychology in many ways merges with their own.

The Pentecostal movement began a little over 100 years ago, during the Azusa Street revival in Los Angeles in 1906. The movement was started by a Black pastor named William Seymour, and it is far more supernatural in its focus than, say, the Southern Baptist or Presbyterian church down the street.

At its heart, Pentecostalism believes that all of the gifts and miracles you read about in the Bible can and do happen today. That means prophecy, speaking in tongues and gifts of healing. Pentecostalism is more working class than the rest of the evangelical world, and Pentecostal churches are often more diverse — far more diverse — than older American denominations. Hispanics in particular have embraced the Pentecostal faith, both in the United States and in Latin America, and Pentecostalism has exploded in the global south.

That long experience has taught me that the future of our nation isn’t just decided in the halls of secular power; it’s also decided in the pulpits and sanctuaries of American churches. Aleksandr Solzhenitsyn wrote that the line between good and evil “cuts through the heart of every human being.” That same line also cuts through the heart of the church.

One Comment by a reader of NYT

Michael Piscopiello

Well, as an atheist focused on the secular world of reality, the differentiation between these religions, as for that matter all religions is meaningless. Religions are a us vs them institutions. Not happy with a particular brand of religion go and create one that serves your purpose. This is what has happened throughout history. Once your remove the mystique of the supernatural, religions are like any other top down organization.

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” Harvard’s Course on Singer Taylor Swift” By Madison Kircher

Fans of Taylor Swift often study up for a new album, revisiting the singer’s older works to prepare to analyze lyrics and song titles for secret messages and meanings.

“The Tortured Poets Department” is getting much the same treatment, and perhaps no group of listeners was better prepared than the students at Harvard University currently studying Ms. Swift’s works in an English class devoted entirely to the artist. The undergraduate course, “Taylor Swift and Her World,” is taught by Stephanie Burt, who has her students comparing Ms. Swift’s songs to works by poets and writers including Willa Cather, Samuel Taylor Coleridge and William Wordsworth.

On Thursday night, about 50 students from the class gathered in a lecture hall on campus to listen to Ms. Swift’s new album. Mary Pankowski, a 22-year-old senior studying history of art and architecture, wore a cream sweatshirt she bought at Ms. Swift’s Eras tour last year. The group made beaded friendship bracelets to celebrate the new album, she said.

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