Xenotransplantation – replacing human organs with ones from animals – has advanced since I reported last fall that the first pig kidney attached to a living human came from Iowa.

Doctors repeated the experiment at least twice, once at the University of Alabama at Birmingham on September 30, 2021 and again at New York University, which conducted the first kidney xenotransplant.

Then, in early January, University of Maryland Medical Center surgeons replaced a 57-year-old man’s failing heart with one from a genetically engineered pig. He has since died.

All the organs came from Revivicor, a division of medical conglomerate United Therapeutics. The first kidney transplanted at NYU came from a pig raised at an Iowa facility operated by Exemplar Genetics, a subsidiary of Sioux Center’s Trans Ova Genetics.

The pigs are engineered to remove three genes that would prompt a human body to reject the transplanted organ. Six human genes that Revivicor inserted into swine DNA are designed to help human bodies accept a transplanted organ.

The genetically modified pigs must be raised in medically conditions avoid exposing them to diseases hogs share with humans. Trans Ova subsidiary Exemplar specializes in providing such settings for research animals.

Although the first NYU kidney came from Iowa, it appears the other pig organs may have come from elsewhere. The Alabama pig was raised at the university. The New Yorker magazine notes that the heart transplanted in Maryland came from a Virginia facility.

Iowa may not have a monopoly on genetically modified hogs for transplant purposes, but the question remain: Is it ethical to turn animals into spare parts stores for humans?