Infection

How to grow toxin-free corn

transgenic corn infected with fungus
GRAIN TRAINING Genetically altered corn infected with Aspergillus fungus (shown) may be able to prevent the fungus from releasing carcinogenic toxins.

Corn genetically engineered to make ninjalike molecules can launch an attack on invading fungi, stopping the production of carcinogenic toxins.

These specialized RNA molecules lie in wait until they detect Aspergillus, a mold that can turn grains and beans into health hazards. Then the molecules pounce, stopping the mold from producing a key protein responsible for making aflatoxins, researchers report March 10 in Science Advances. With aflatoxins and other fungal toxins affecting up to 25 percent of crops worldwide, the finding could help boost global food safety, the researchers conclude.

“If there’s no protein, no toxin,” says study coauthor Monica Schmidt, a plant geneticist at the University of Arizona in Tucson.

Schmidt and colleagues used a technique called RNA interference, which takes advantage of a natural defense mechanism organisms use to protect against viruses. The researchers modified corn to make it produce short pieces of RNA that match up to sections of an RNA in the fungus made from the aflC gene. That gene encodes the first step of a biochemical pathway that the fungus uses to make the toxins. When the corn’s modified RNAs match up with those of the fungus, that triggers Aspergillus to chop up its own RNA, preventing a key protein, and thus the toxin, from being made.

Then, the team infected both…

Certain birth defects are on the rise since Zika arrived in the U.S.

stethoscope on a pregnant woman's belly
ZIKA BABIES Zika infection during pregnancy substantially raises the risk that the baby will have certain birth defects, such as microcephaly and other brain deformations. A new CDC study quantifies that impact in the United States.

Certain birth defects were 20 times more prevalent in babies born to Zika virus–infected mothers in the U.S. in 2016 than they were before the virus cropped up in the United States, a CDC study suggests. The finding strengthens the evidence that a mother’s Zika infection during pregnancy raises her baby’s risk of microcephaly and other…