Happy New Year: Looking Back at 2016 Research Highlights

Science Breakthroughs of the Year 2016Happy New Year! While everyone was busy getting ready for the holidays, the journal Science announced its annual compendium of scientific Breakthroughs of the Year. If you missed it, the winner for 2016 was the detection of gravitational waves—tiny ripples in the fabric of spacetime created by the collision of two black holes 1.3 billion years ago! It’s an incredible discovery, and one that Albert Einstein predicted a century ago.

Among the nine other advances that made the first cut for Breakthrough of the Year, several involved the biomedical sciences. As I’ve done in previous years (here and here), I’ll kick off this New Year by taking a quick look of some of the breakthroughs that directly involved NIH support:

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Talking Music and Science with Yo-Yo Ma

It’s not every day that an amateur guitar picker gets to play a duet with an internationally renowned classical cellist. But that was my thrill this week as I joined Yo-Yo Ma in a creative interpretation of the traditional song, “How Can I Keep from Singing?” Our short jam session capped off Mr. Ma’s appearance as this year’s J. Edward Rall Cultural Lecture.

The event, which counts The Dalai Lama, Maya Angelou, and Atul Gawande among its distinguished alumni, this year took the form of a conversation on the intersection of music and science—and earned a standing ovation from a packed house of researchers, patients, and staff here on the National Institutes of Health (NIH) campus in Bethesda, MD.

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Out of Africa: DNA Analysis Points to a Single Major Exodus

View of Africa from space

Credit: NASA

If you go back far enough, the ancestors of all people trace to Africa. That much is clear. We are all Africans. But there’s been considerable room for debate about exactly when and how many times modern humans made their way out of Africa to take up residence in distant locations throughout the world. It’s also unclear what evolutionary or other factors might have driven our human ancestors to set off on such a perilous and uncertain journey (or journeys) in the first place.

By analyzing 787 newly sequenced complete human genomes representing more than 280 diverse and understudied populations, three new studies—two of which received NIH funding—now help to fill in some of those missing pages of our evolutionary history. The genomic evidence suggests that the earliest human inhabitants of Eurasia came from Africa and began to diverge genetically at least 50,000 years ago. While the new studies differ somewhat in their conclusions, the findings also lend support to the notion that our modern human ancestors dispersed out of Africa primarily in a single migratory event. If an earlier and ultimately failed voyage occurred, it left little trace in the genomes of people alive today.

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Summer Reading Suggestions from Scientists: Shirley Tilghman

Summer Reading

 

Non-Science Selection:

Viet Thanh Nguyen, The Sympathizer. In his brilliant debut novel, this American writer, who was born in Vietnam, uses the end and aftermath of the Vietnam War as a dramatic backdrop to explore the nature of identity and conflicts of loyalty, The anonymous narrator is a jumble of identities—the son of a Vietnamese woman and a French priest; a Communist working undercover as an aide to a South Vietnamese general; and a blood brother of both a C.I.A. assassin and a Vietcong leader. He believes in the revolution, but is haunted when he is required to murder in its name, and, ultimately, is abandoned by its leaders.

The narrative begins with a vivid portrayal of the last days of the fall of Saigon, as the narrator works feverishly to extract himself, his general and family off the rooftop of the American embassy. They ultimately land in California, where the general immediately begins to plot his return to Saigon. The narrator is hired to advise a filmmaker (referred to only as “the auteur,” but clearly meant to be Francis Ford Coppola) on a film about the war. The narrator believes he has been hired to give an authentic voice to the Vietnamese, whose sufferings and struggle have largely been untold in the West, but he fails in tragicomic fashion. In the end, the narrator is torn in two by his competing loyalties to politics and friendship. This is a deeply moving story of a young man in search of meaning in his life.

Science Selection:

Jonathan Weiner,The Beak of the Finch. The Pulitzer Prize winner for non-fiction in 1995, this masterful book tells the 25-year story of Peter and Rosemary Grant’s study of evolution in real time in the Galapagos Islands. Beginning in 1973, the Grants, who recently retired from the faculty of Princeton University, camped several months every year on a barren rock (Daphne Major) in the Galapagos, meticulously documenting the changes in size and shape of the beaks of Darwin’s famous finches in response to changes in climate. Thanks to the dramatic 1982-83 El Nino, the Grants were able to show that as the normally arid climate, which selected for finches with sturdy short beaks that are good at cracking dry hard seeds, became tropical, finches with long narrow beaks that could drink nectar from the now-abundant vegetation came to predominate. Natural selection in action! In the course of telling this extraordinary story of scientific inquiry, Weiner writes clearly and engagingly about how Charles Darwin and Alfred Russel Wallace developed the theory of natural selection, and why it is the cornerstone on which all of biology rests.Line

Shirley Tilghman

Shirley Tilghman
Credit: Denise Applewhite

Shirley M. Tilghman, PhD is president emerita and professor of molecular biology at Princeton University. She is well known for her scientific achievements as a mammalian developmental geneticist and for her national leadership on behalf of women in science. Her many accolades include: a Lifetime Achievement Award from the Society for Developmental Biology, the Genetics Society of America Medal, and the L’Oreal-UNESCO Award for Women in Science.

Gene Duplication: New Analysis Shows How Extra Copies Split the Work

Word cloudThe human genome contains more than 20,000 protein-coding genes, which carry the instructions for proteins essential to the structure and function of our cells, tissues and organs. Some of these genes are very similar to each other because, as the genomes of humans and other mammals evolve, glitches in DNA replication sometimes result in extra copies of a gene being made. Those duplicates can be passed along to subsequent generations and, on very rare occasions, usually at a much later point in time, acquire additional modifications that may enable them to serve new biological functions. By starting with a protein shape that has already been fine-tuned for one function, evolution can produce a new function more rapidly than starting from scratch.

Pretty cool! But it leads to a question that’s long perplexed evolutionary biologists: Why don’t duplicate genes vanish from the gene pool almost as soon as they appear? After all, instantly doubling the amount of protein produced in an organism is usually a recipe for disaster—just think what might happen to a human baby born with twice as much insulin or clotting factor as normal. At the very least, duplicate genes should be unnecessary and therefore vulnerable to being degraded into functionless pseudogenes as new mutations arise over time

An NIH-supported team offers a possible answer to this question in a study published in the journal Science. Based on their analysis of duplicate gene pairs in the human and mouse genomes, the researchers suggest that extra genes persist in the genome because of rapid changes in gene activity. Instead of the original gene producing 100 percent of a protein in the body, the gene duo quickly divvies up the job [1]. For instance, the original gene might produce roughly 50 percent and its duplicate the other 50 percent. Most importantly, organisms find the right balance and the duplicate genes can easily survive to be passed along to their offspring, providing fodder for continued evolution.

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