Blocking aflatoxin at the gene level

Aflatoxin, the most potent carcinogen in nature, contaminates about 25% of the global food supply. This form of mycotoxin can cause environmental damage, yield loss, and human illness. People can be exposed to aflatoxin by eating contaminated plants, such as peanuts, or by eating meat from animals that have consumed aflatoxin-tainted feed. Farm workers can be exposed by inhaling dust from contaminated crops. Exposure to aflatoxin is linked to an increased risk of liver cancer.

Traditional prevention treatments focus on killing the fungi that produce the toxic compound, but the treatments can harm crops and other hosts. Instead, Wisconsin researchers are working at the genetic level to prevent aflatoxin from developing in the first place.

They were able to produce fungi missing the wetA regulator, which is necessary for the fungi to produce intact spores. In fact, of the nearly 12,000 genes in Aspergillus flavus, one of the fungi that produce aflatoxin, half are affected by the WetA regulator. With this information, the researchers are now exploring ways to target WetA while avoiding harsh side effects. Eventually the treatments could be spread on farm fields to prevent fungal infestation and aflatoxin.