That doesn't mean Americans will be eating cloned meat any time soon, stressed Dr. Stephen Sundlof, the FDA's veterinary medicine chief.
The FDA wants public reaction to its assessment of cloning's impact on the food supply before it decides if cloned farm animals will require government approval before being sold as food — a decision expected to take another year.
Meanwhile, the industry has voluntarily agreed for the last several years not to allow any products from cloned animals into the food supply, a moratorium Sundlof said the FDA expects to be upheld until it settles the issue.
The agency last year asked the prestigious National Research Council to study foods made from cloned animals. The council, an independent group that advises the government on scientific issues, concluded that cloned meat and other products seem safe.
The FDA will look two issues: Are the animals themselves healthy, and are the products nutritionally indistinguishable from those produced by non-cloned animals?
By its very definition, a successfully cloned animal should be no different from the original animal whose DNA was used to create it.
But the technology hasn't been perfected, meaning many attempts end in birth defects. The FDA acknowledged concern about the animals' welfare in an 11-page summary of its initial review, to be posted on the agency's Web site Friday.
"The frequency of live normal births appears to be low, although the situation appears to be improving as the technology matures," the review says.
Still, cloning-related birth defects aren't that different from problems seen in the early days of other assisted reproduction techniques in farming, the FDA says.
When it comes to animals that are born healthy, there are some differences between the cloned and non-cloned at young ages. "But as the animal matures, they become indistinguishable," Sundlof said.
If it concludes cloned food products are safe, the FDA then must decide if cloning is just another form of assisted reproduction on the farm — which it doesn't regulate — or if each product will require specific approval before selling.
Although preliminary, the FDA's findings are causing consternation for some consumer advocates.
The FDA hasn't yet completed writing the 300-page scientific review on which the summary is based, even though the agency is asking its scientific advisers to critique the risk assessment next week. How, critics wonder, can anyone be confident of the FDA's review of such an important matter on the basis of 11 pages of vague information?
In addition, the FDA hasn't yet considered the societal reaction to using cloned animals for food, something the National Research Council specifically urged addressing, said Carol Tucker Foreman of the Consumer Federation of America.
"Sixty percent of the American people flat out oppose cloning, so there are scientific issues here, but there are a lot of other issues to consider as well," she told CBS Radio News.
Nor is it clear that the FDA has the legal authority to stop a cloner emboldened by these preliminary findings from breaking the moratorium and selling cloned products, she said.
"The FDA can take no action against them if they decide to go ahead and move forward, and yet this is only a preliminary report," Foreman, CFA's Director of Food Policy, said.
She accused the FDA of pulling a Halloween trick on consumers.
"Most Americans find cloning animals to be a pretty scary proposition," she said.
Consumer reaction could prove key to whether food producers want to invest in cloning technology or not. Foods that are genetically modified face trade barriers overseas despite FDA assurances that those now sold are safe. While cloning means a genetic copy, not genetic modification, public understanding of biotechnology is sketchy.
"If these products are safe, is the consumer confident in that?" asked Stephanie Childs of the Grocery Manufacturers of America. "We're definitely examining this issue very closely."