Barbecue can return to the menu for individuals with “alpha-gal” syndrome — severe allergic reactions to the alpha-galactose saccharide found in red meat — with FDA approval Monday of pigs engineered to lack an enzyme considered key to the condition.
Developed by a company called Revivicor, the “GalSafe” pigs might also have therapeutic potential as sources of xenograft organs and tissues, the FDA said. Another example the agency offered was heparin “free of detectable alpha-gal sugar.”
The decision represents the FDA’s first approval of “intentional genomic alteration” (IGA) in an animal that may be used both for food and medical use, the agency said. However, any use of the animals for xenotransplant or other therapeutic applications must undergo a separate regulatory review; at this point, only meat for the dining table has the agency’s OK.
It’s not the first genetically engineered food animal, though — that honor belongs to AquaBounty’s salmon with a growth hormone gene and certain regulatory elements added from other species.
In both cases, the FDA determined that foods derived from the modified creatures posed no more risk to humans or the environment than their unmodified counterparts.
In the case of Revivicor’s swine, the agency said, “conditions under which GalSafe pigs will be kept are far more stringent than those for conventionally farmed pigs. Additionally, no animal safety concerns were noted for GalSafe pigs beyond those that would be expected in well-managed, commercial swine operations.”
The specific alteration in the pigs is to delete the gene for alpha-1,3-galactosyltransferase, which attaches alpha-galactose sugars to cell surfaces.
Alpha-gal syndrome appears to originate with bites from certain tick species. People thus sensitized then develop allergic reactions to foods containing alpha-galactose, such as beef, lamb, and other red meats, in addition to pork. Although considered rare, it’s also believed to be responsible for up to half of anaphylactic reactions with no obvious trigger.
At least initially, Revivicor plans to sell pork from its GalSafe herd only via mail order, not in supermarkets, the FDA said.