The first man to receive a genetically modified pig kidney has been allowed to leave the hospital.
The 62-year-old man was discharged two weeks after emergency surgery at Massachusetts General Hospital (MGH).
Organ transplants from genetically modified pigs have not succeeded in the past.
But the success of this procedure so far has been hailed by scientists as a historic milestone in the field of transplantation.
In a statement, the hospital said the patient, Richard "Rick" Slayman of Weymouth, Massachusetts, had been battling kidney disease and needed the transplant to save his life.
His doctors successfully transplanted the genetically modified pig kidney into his body in a four-hour surgery on March 16.
They said Mr. Slayman's kidney is now functioning well and that he does not need dialysis treatment.
In a statement, Mr. Slayman expressed his joy at the doctors' decision to allow him to leave the hospital.
It is "one of the happiest times" of his life, he said.
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