A gene that helps mammals break down certain toxic chemicals appears to be faulty in marine mammals — potentially leaving manatees, dolphins and other warm-blooded water dwellers more sensitive to dangerous pesticides.
The gene, PON1, carries instructions for making a protein that interacts with fatty acids ingested with food. But that protein has taken on another role in recent decades: breaking down toxic chemicals found in a popular class of pesticides called organophosphates. As the chemicals drain from agricultural fields, they can poison waterways and coastal areas and harm wildlife, says Wynn Meyer, an evolutionary geneticist at the University of Pittsburgh.