Why was a pig kidney transplanted into a living human?

The answer

In March 2024, surgeons at Massachusetts General Hospital transplanted a genetically modified pig kidney into 62-year-old Rick Slayman, marking the first such procedure in a living patient. The pig, developed by eGenesis, had 69 genomic edits: removing pig genes that cause immune rejection, adding human genes for compatibility, and inactivating porcine endogenous retroviruses. Slayman survived nearly two months before passing from unrelated causes. Previously, in January 2022, surgeons at the University of Maryland transplanted a pig heart into David Bennett, who survived 60 days. Over 100,000 Americans await organ transplants, with 17 dying daily. Xenotransplantation using gene-edited pigs could potentially eliminate this shortage entirely, though long-term safety data remains limited.