BOB HIRSHON (host):
Mad cow no more. I’m Bob Hirshon and this is Science Update.
Scientists have designed cows that likely can’t catch mad cow disease. The brain disease starts with a misshapen protein that then spreads the defect to its normal neighbors. But these genetically engineered cows don’t make that normal protein. Reproductive biologist Jim Robl is president of Hematech, which led the collaboration. He says that despite lacking the protein, the cows seem perfectly healthy.
JAMES ROBL (Hematech, Inc.):
And it’s a protein that is evolutionarily conserved, indicating that it’s an important protein. However, at two years of age the cows are indistinguishable from normal cows, so at this moment we really don’t know what this protein actually does.
Robl’s company plans to use the cows to develop medical products. Whether they’re ever used for food, he says, depends on public opinion and the beef industry.
I’m Bob Hirshon, for AAAS, the science society.