Genetically Engineered Pig Kidney Successfully Transplanted to Human Patient In World First

Every year, many people die while waiting on the organ donor list. The reason? They have to wait for someone else to die in order to receive an organ. Scientists and doctors have been trying to figure out how to alleviate this problem for quite some time – and they may have just found a solution. Surgeons in New York City have just completed the first-ever successful kidney transplant from a pig to a human. (1)

First-Ever Successful Pig Kidney Transplant

There’s no doubt about it, we need a long-term, sustainable solution to the organ donation shortage. Currently, there are over 100,000 people on the organ donation waiting list, and about 90,000 of them are waiting for a kidney. After decades of experimentation with using animal organs, doctors and scientists at the NYU Langone Health in New York City finally succeeded. They successfully transferred the first pig kidney that the human body didn’t immediately reject. (2)


Researchers performed the kidney transplant on September 25, called xenotransplantation. The procedure took two hours to complete. The recipient of the kidney was a person who had been declared brain dead with signs of kidney dysfunction and was on life support. Their family gave permission to attempt the transplant before removing the person off of life support.


Read: If Your Kidneys Are in Danger, Your Body Will Give You These 21 Signs


The Kidney Transplant Procedure

The researchers attached the kidney to the patient’s blood vessels, however, they kept the kidney outside of her body. This way, they would have continued access to the organ. The experiment lasted over a period of three days.


As they came to the end of the three-day experiment, the researchers noted that the kidney seemed to be functioning just as a human kidney would. It produced a normal level of urine and there were no signs of rejection. The lead surgeon Doctor Robert Montgomery said the results were even better than he expected. He called it “a transformative moment in organ transplantation”.


“The kidney turned a beautiful pink color and immediately urine started pouring out of the ureter,” he said. “…There was complete silence for a few minutes while we were sort of taking in what we were looking at, which was incredible. It was a kidney that was immediately functioning.”

The pig in question had its genes altered so that its tissues no longer contained a molecule researchers know causes almost immediate rejection. This pig is known as a GalSafe pig and is approved by the FDA.


An Incredible Scientific Achievement

Chief clinical officer of LiveOnNY Chad Ezzel couldn’t be happier. LiveOnNY is a non-profit organization that facilitates organ and tissue donation in New York City. Naturally, this is very hopeful news for anyone waiting on the organ donor list.


“We are entering a new era for our field and this will give new hope to those on our wait list as this important research moves forward,” he said.

Montgomery and his team are hoping that the NYU kidney transplant will pave the way for trials in humans with late-stage kidney failure within the next year or two. They also see many other applications for tissues from GalSafe pigs, from heart valves to skin grafts. Naturally, they still need to do some trials that last longer than three days. These future tests could be short-term solutions for critically ill patients while they wait for human kidneys, or they could also be a permanent solution. 


“For a lot of those people, the mortality rate is as high as it is for some cancers, and we don’t think twice about using new drugs and doing new trials (in cancer patients) when it might give them a couple of months more of life,” Montgomery explained.

Why Pigs?

Genetically, pigs are actually remarkably similar to humans. The size of their organs also happens to be the right fit. Pigs are also typically raised for meat consumption. The general population tends to have fewer moral or ethical dilemmas surrounding using pig organs versus primates. The removal of that one organ-rejecting molecule-creating gene means that pigs are the perfect non-human candidate.


“When you cross species with a transplant and it happens immediately, humans have preformed antibodies circulating in their blood that are directed towards most of them towards a single molecule that was lost during evolution from pig to man,” Montgomery said. “And so when you put an organ from a pig into a human, it’s immediately rejected.” 

A heart transplant recipient himself, he understands the urgency for more readily available organs. It is exciting to think of the number of lives that could be saved and extended from this new possibility.

Keep Reading: This Artificial Kidney Could One Day Eliminate The Need For Kidney Dialysis


  1. U.S. surgeons successfully test pig kidney transplant in human patient.” Reuters. Nancy Lapid. October 20, 2021.
  2. Surgeons tested a pig kidney transplant in a human patient — and for the first time, it worked.” CBS News. Li Cohen. October 20, 2021.
Julie Hambleton
Freelance Writer
Julie Hambleton has a BSc in Food and Nutrition from the Western University, Canada, is a former certified personal trainer and a competitive runner. Julie loves food, culture, and health, and enjoys sharing her knowledge to help others make positive changes and live healthier lives.