Research

Random mutations play large role in cancer, study finds

GROWING PAINS As cells divide and grow to replenish and repair organs, accidental mutations may crop up in cancer-associated genes. A new study suggests such random mistakes are the source of 66 percent of mutations in cancer cells (illustrated here) across the board.

Researchers have identified new enemies in the war on cancer: ones that are already inside cells and that no one can avoid.

Random mistakes made as stem cells divide are responsible for about two-thirds of the mutations in cancer cells, researchers from Johns Hopkins University report in the March 24 Science. Across all cancer types, environment and lifestyle factors, such as smoking and obesity, contribute 29 percent of cancer mutations, and 5 percent are inherited.

That finding challenges the common wisdom that cancer is the product of heredity and the environment. “There’s a third cause and this cause of mutations is a major cause,” says cancer geneticist Bert Vogelstein.

Such random mutations build up over time and help explain why cancer strikes older people more often. Knowing that the enemy will strike from within even when people protect themselves against external threats indicates that early cancer detection and treatment deserve greater attention than they have previously gotten, Vogelstein says.

Vogelstein and biomathematician Cristian Tomasetti proposed in 2015 that random mutations are the reason some organs are more prone to cancer than others. For instance, stem cells are constantly renewing the intestinal lining of the colon, which develops tumors more often than the brain, where cell division is uncommon. That report was controversial because it was interpreted as saying that most cancers are the result of “bad luck.” The analysis didn’t include breast and prostate cancers. Factoring in those common cancers might change the results, some scientists said. And because the researchers looked at only cancer within the United States, critics charged that the finding might not hold up when considering places around the world where different environmental factors, such as infections, affect cancer development.

In the new study, Vogelstein, Tomasetti and Hopkins colleague Lu Li examined data from 69 countries about 17 types of cancer, this time including breast and prostate. Again, the researchers found a strong link between cancer and tissues with lots of dividing stem cells. The team also used DNA data and epidemiological studies to calculate the proportions of mutations in cancer cells caused by heredity or environmental and lifestyle factors. Remaining mutations were attributed to random errors — including typos, insertions or deletions of genes, epigenetic changes (alterations of chemical tags on DNA or proteins that affect gene activity) and gene rearrangements. Such errors unavoidably happen when cells divide.

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Chance cancer

For many organs, more of the mutations that lead to cancer come from random mistakes in DNA…

Watch Hilariously Awkward Robots Rap About Their Machine-Learning Skills

How do robots learn to act more like humans? Not by rapping. Researchers from Telecommunications Research Institute in Kyoto, Japan recently summarized their latest work [PDF] by having two robots show off their lyrical skills, and boy, is it cringe-worthy (Gizmodo called it “agonizingly awkward”) and amazing.

Two robots, Robovie and the super creepy android ERICA, rap their way through a parody of the Sugarhill Gang’s “

Yale Researchers Find That Autism Genes Helped Us to Become Smarter

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Those with autism face distinct challenges. These usually have to do with certain social deficits. That might be why the results of a new study appear a bit puzzling. Genes linked to autism spectrum disorders (ASD) were actually preserved through the process of evolution, Yale researchers concluded. These genes actually made us smarter.

If you find these results strange, consider the large numbers of scientists and engineers known to have Asperger’s syndrome. There are autistic savants as well, as the movie Rain Man can attest, which was based on a true story. Or perhaps you’ve seen the work of mind-blowing artist Stephen Wiltshire, who can draw panoramic scenes of whole cities with perfect detail, from his memory alone.

This was a genome-wide study, zeroing in on gene variants associated with ASD. Researchers examined 5,000 cases of autism and analyzed the genome of each participant. They focused on evolutionary gene selection, particularly on which genes were positively selected. One clue which led researchers to these findings was that, more genes associated with autism were preserved by evolution than would have been through sheer randomness.

Autistic…

Scientists move closer to building synthetic yeast from scratch

Saccharomyces cerevisiae yeast
BUDDING STAR With five more synthetic chromosomes built, scientists are closer to creating a synthetic genome for Saccharomyces cerevisiae yeast (shown).

Synthetic yeast is on the rise.

Scientists have constructed five more yeast chromosomes from scratch. The new work, reported online March 9 in Science, brings researchers closer to completely lab-built yeast.

“We’re doing it primarily to learn a little more about how cells are wired,” says geneticist Jef Boeke of the New York University Langone Medical Center. But scientists might also be able to tinker with a synthetic yeast cell more efficiently than a natural one, allowing more precise engineering of everything from antiviral drugs to biofuels.

Boeke was…

9 Up-Close Scientific Images from the Wellcome Image Awards

Each year, the Wellcome Image Awards highlight some of the most fascinating scientific images from around the world, as chosen by a panel of experts from the fields of science communications and medicine. The awards go to photographers and researchers who create “informative, striking and technically excellent images that communicate significant aspects of healthcare and biomedical science,” according to the Wellcome Trust, a biomedical research charity based in the UK. Here are nine of this year’s winning images:

ZEBRAFISH EYE AND NEUROMASTS

Ingrid Lekk and Steve Wilson, University College London

In this 4-day-old zebrafish embryo, a certain gene expressed in the lens of the eye and other parts of the visual system glows red when it’s activated. You can see the lens of the eye, the head, and neuromasts (those red dots around the rim of the image) glowing red, while the nervous system glows blue.

BLOOD VESSELS OF THE AFRICAN GREY PARROT

This image was created using a 3D reconstruction of a euthanized parrot. It models the system of blood vessels in the parrot’s head and neck down to the capillary level.

INTRAOCULAR LENS IRIS CLIP

Mark Bartley, Cambridge University Hospitals NHS Foundation Trust

Iris clips can treat nearsightedness, cataracts, and other eye issues. This photo shows an iris clip fitting on the eye of a 70-year-old patient. He regained nearly all his vision after the surgery.

BRAIN-ON-A-CHIP

Collin…

Rapid Ebola test to detect early infection in the works

Ebola virus
TEAM PLAYERS Researchers are designing antibody pairs that can help detect the Ebola virus (shown) sooner.

WASHINGTON — Diagnosing Ebola earlier is becoming almost as easy as taking a home pregnancy test.

Scientists are developing antibodies for a test that can sniff out the deadly virus more quickly and efficiently than current tests, researchers reported February 6 at the American Society for Microbiology Biothreats meeting.

Detecting Ebola’s genetic material in patients’ blood samples now takes a full day and requires access to a specialized laboratory. Simpler and speedier tests are available. They use antibodies — specialized proteins that latch onto and flag virus particles — and work somewhat like a pregnancy test. Within…