Doctors have found a new way to help people whose kidneys have failed, using kidneys taken from genetically altered pigs. In one recent case in the United States, a man lived without needing dialysis for 271 days after receiving a pig kidney, before later getting a human kidney. This is the longest such gap ever recorded for a living patient, and it has encouraged scientists to believe that animal organs could one day ease the huge shortage of human donor organs.

India is now taking steps in this direction too. Sir Ganga Ram Hospital in Delhi has set up a special department focused on this science, called xenotransplantation, and the government's health ministry is working on rules to guide its use in the country.

What is xenotransplantation?

Xenotransplantation simply means transplanting organs, tissues or cells from one species into another, for example, from a pig into a human. The idea has existed for decades, but it did not work well in the past because the human body would immediately attack and reject animal tissue.

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What has changed now is genetic engineering. Scientists can edit the DNA of pigs before they are even born, so their organs are far less likely to be rejected once placed inside a human body.

How a pig kidney is made suitable for humans

Pigs used for this purpose are not ordinary farm pigs. They are bred and raised under strict, controlled conditions specifically for this purpose.

Scientists use a gene-editing tool called CRISPR to switch off certain pig genes. These genes normally produce substances that trigger a strong reaction from the human immune system. By removing them, the organ becomes less likely to be attacked by the body's defences.

At the same time, researchers add certain human genes into the pig's genetic code. These help control processes such as blood clotting, immune reactions and a part of the immune system called the complement system, all of which can cause organ rejection if left unchecked.

Scientists also work to deactivate viruses that occur naturally in pig DNA, since there are concerns these could potentially infect humans.

Pigs are chosen for this work mainly because their organs are roughly the same size as human organs, they reproduce quickly, and their genes can be modified relatively easily.

The case that changed the outlook

The most notable example so far involves a 66-year-old man named Tim Andrews. In January 2025, he received a genetically modified pig kidney developed by the biotech company eGenesis, as part of a special programme approved by American health regulators.

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The kidney began working straight away and kept him off dialysis for 271 days. However, he did experience one early episode of organ rejection, which doctors managed to treat. Later, after his medication to suppress his immune system was reduced because of an infection, the kidney developed damage and swelling, and eventually stopped working.

In January 2026, Andrews received a kidney from a deceased human donor instead, making him the first known patient to move from a pig kidney transplant to a human kidney transplant. Importantly, doctors found no sign that pig diseases had passed on to him, and his body accepted the human kidney without complications linked to the earlier pig organ.

What scientists are learning

This case showed both the promise and the current limits of the technology. Researchers, including experts involved in India's new programme, are now studying why some patients develop problems such as protein leaking into their urine after receiving pig kidneys.

Because the donor pigs are genetically engineered, scientists can use lessons from cases like this to improve the next generation of pigs, rather than simply hoping for a better match with a different donor.

Why India is paying attention

India faces a severe shortage of organs. As of March 2026, nearly 90,000 people were waiting for major organ transplants. Although India carried out over 20,000 transplants in 2025, its highest number yet, only about 18 percent of these came from deceased donors. This means the country still relies heavily on living donors, particularly for kidneys.

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If pig organs can eventually be proven safe and affordable, they could offer another source of organs, reducing the long waiting times many patients currently face.