Friday, October 20, 2006

Eating clones

The FDA is getting close to approving meat and milk from cloned animals. I’m not particularly worried about the safety of cloned foods. It’s no different from eating animals that are identical twins. We’ve had the technology for twenty years or so to produce clones from embryos, producing two or three or four identical babies instead of just one, and those critters aren’t particularly unsafe. Furthermore, due to the difficulty and expense involved in cloning adult animals, I doubt we’ll see many of them, and there is zero chance they will make it into a feedlot and thence to the meat case at your local grocery store—they will be far too valuable to eat.

The bigger danger is loss of genetic diversity. Because clones are identical twins, they have identical immune systems, and identical disease susceptibility. Consider a clone that we already eat—the humble banana. The Cavendish banana variety is productive, tasty, travels well, and seedless. They are propagated by digging up shoots from mature plant and putting them in the dirt somewhere else. Every single yellow banana you’ve ever eaten is a clone, genetically identical to every other yellow banana (there are other varieties, but the Cavendish is the biggie). Every single Cavendish banana is strongly susceptible to Panama Disease and Black Sigatoka, which are fungal diseases. Panama Disease wiped out the Gros Michael banana variety in the 1950s, putting the Cavendish on top. Losing the worldwide banana supply would be a loss for us, but it would be a disaster for the tropical banana farmers and farm workers.

Now imagine a world full of cloned dairy cattle, or chickens, or hogs. We are close to that now in the poultry industry—commercial birds aren’t clones, but they have very little genetic diversity. The avian flu that is causing so much panic isn’t being incubated and mutated in wild populations or small family flocks. It’s a byproduct of huge barns full of inbred birds. That is the true danger of cloning.

No comments: